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IGCSE · Pearson Edexcel · 4MA1

Use trapezium and kite properties with correct diagonals

Use marked trapezium and kite properties, distinguish their special cases and reject data that fail the advertised geometric conditions.

Section 4.2 · Polygons

Pearson 4MA1 · Shared Geometry · Polygons · Foundation 4.2C · inherited by Higher
Exam scope and assessment notes

Foundation and Higher share all seven section4.2 requirements A–G. The Higher table says See Foundation Tier; there are no additional H4.2 rows. These seven original lessons teach polygon names, convex/concave quadrilateral sums, all six named quadrilateral families, general polygon sums, regular interior/exterior angles and congruence correspondence. F:4.2C requires both the parallelogram/rectangle/rhombus/square lesson and the trapezium/kite lesson with substantive teaching, a worked example and every Guided, Independent and Transfer stage. F and G are two distinct published rows; the same substantive congruence lesson links both without inventing a third requirement. Seven lessons and28 selected seed cases are StudyForA’s design, not a syllabus-prescribed count. Rhombus/square diagonal endpoint-angle bisection, kite symmetry-diagonal endpoint-angle bisection and isosceles-trapezium equal diagonals are conservative standard-property breadth under the broad C wording, not new verbatim syllabus bullets or an assertion that the public book chart enumerates each one. Use labelled boundary order, actual interior/reflex arcs, given or justified parallel/equal-side/right-angle marks and geometric reasons before equations. Diagrams need not be to scale; do not measure them unless instructed. Use the local exactly-one-parallel-pair trapezium convention and different-length adjacent-pair kite fixtures; the sources do not settle every inclusive naming convention. Keep rectangle equal diagonals, rhombus perpendicular/bisected diagonals, square45° endpoint halves and kite one-way diagonal bisection distinct. General simple-polygon sums include checked concave triangulation; crossed boundaries, holes and curved outlines are outside these cases. Regular examples use consistent convex exterior turns and exact integer side-count checks; unknown-n full outlines follow the deduction, while impossible marked data remain condition cards. Congruence preserves full corresponding shape and size under turns/reflections, including reflex interiors; equal area, perimeter or angles alone is insufficient. A fixed reference picture and a correct number do not establish that a learner drew or justified the configuration. Written work is not automatically marked. Attempt acknowledgements and revealed references do not award marks or establish mastery. These structural links are not exhaustive subskill approval; specialist approval and formal assessment validation remain unestablished. Section4.3 symmetry,4.4 measurement/bearings,4.5 formal instrument constructions,4.11 similarity and the full H4.7A reasoning scope remain separate. Local symmetry-diagonal use is not complete symmetry coverage; no blanket formal-proof waiver is imported from unrelated circle-theorem notes. The wider Maths A course remains incomplete. Publisher book navigation is separate evidence: Book1 Shape and Space1 has literal F4.2B/C chapter and Hub19 Geometry of Shapes2 tags, not A; map60–99 and proof start60/next100 agree. Book2 Shape and Space6 has literal D/E chapter tags, with Hub59 Angles in Polygons2 for D and Hub58 Angles in Polygons1 for E; map128–160 and proof start128/next161 agree. The map associates F/G with Shape and Space7 pages223–248, while the public proof chapter starts222 and its next chapter starts248; proof contents instead place Congruent shapes129 and Similar shapes147 in Shape and Space6. Preserve that unresolved topic/page conflict rather than moving tags silently. Hub85 Similarity1 literally tags F4.2F and F4.11A, not G. A has no literal chapter/Hub tag and G has no literal Hub tag. Only selected Book1 public uncorrected proof body pages69–71 were inspected; Book2 relevant chapters are contents-only evidence in the public sample. Full final-book and Teaching Hub body/pagination alignment remains unverified; chapter links confer no full-book or modular teaching credit.

Before you begin

  • Use co-interior angles between parallel lines and the quadrilateral 360° sum.
  • Read adjacent equal-side marks and identify opposite vertices.
  • Solve linear equations and add labelled segment lengths.

Work on paper. Try each question before revealing help, and explain why your method works.

Quick readiness check

In kite PQRS, equal adjacent pairs meet at P,R. PR and QS meet at T, with PT=8 cm,TR=5 cm,QT=3 cm. Which statement follows?

What you will learn

  • Use co-interior angle pairs in a trapezium and the additional equal-base-angle properties of an isosceles trapezium.
  • Locate the equal opposite-angle pair and correctly bisected diagonal in a kite.
  • Check both the angle total and the named family conditions before accepting a proposed diagram.

Use two separate labelled panels. Panel 1: right trapezium ABCD has AB∥DC,A=D=90°,B=64°. Mark the parallel pair and find C. Panel 2: kite EFGH has EF=EH and FG=GH, with those pair lengths different; E=76°,G=104°. Mark the two adjacent equal-side pairs and find F,H. Keep each angle arc inside its named polygon. In the kite draw its symmetry diagonal EG, mark its equal angle parts at E and G, and calculate those four parts.

Draw or copy each labelled boundary on paper. Keep stated side lengths, selected interior/reflex/exterior arcs, parallel arrows and equality marks. Give geometric reasons before equations and substitute back. Exact givens determine deductions; screen diagrams are illustrative and must not be measured for an exact answer.

Panel 1: ABCD

Panel 1: ABCDOriginal labelled geometry. Use the stated givens, selected interior or exterior arcs and named relationships; do not measure screen pixels. Solved conclusions and derived property notes remain hidden until an attempted comparison.α1α2α3α4ABCD
  • α1 · arc-1: given 90°
  • α2 · arc-2: given 64°
  • α3 · arc-3: given ?
  • α4 · arc-4: given 90°

Panel 2: EFGH

Panel 2: EFGHOriginal labelled geometry. Use the stated givens, selected interior or exterior arcs and named relationships; do not measure screen pixels. Solved conclusions and derived property notes remain hidden until an attempted comparison.α1α2α3α4EFGH
  • α1 · arc-1: given 76°
  • α2 · arc-2: given ?
  • α3 · arc-3: given 104°
  • α4 · arc-4: given ?
Original fixed StudyForA polygon exploration · shared Foundation content inherited by Higher. Complete rigid rotations/reflections preserve labels and relationships. Different side-tick, angle-dot and arrow counts distinguish separate equality/parallel groups. Default drawings are illustrative; common-scale comparison panels retain size differences. Internal coordinates are drawing machinery, not a requirement to use trigonometry. Fixed drawings support3–20 sides; the separate numeric count check stops above1000000 for reliable precision. These are tool limits, not mathematical domains. This is not an unrestricted polygon parser, formal proof checker, instrument-construction course or automatic marker. Constructions4.5, full symmetry4.3, wider H4.7 reasoning, similarity4.11 and transformation5.2 coverage remain separate. Full-book alignment, specialist approval and formal assessment validation remain unestablished.

Use the actual parallel pair in a trapezium

In these examples a trapezium has exactly one pair of opposite parallel sides. If ABCD is in boundary order and AB∥DC, the non-parallel side AD is a transversal, so A+D=180°. The other non-parallel side BC gives B+C=180°. Name the side that acts as the transversal rather than adding whichever angles look adjacent on the page.

A general trapezium does not have to have equal non-parallel sides or equal base angles. An isosceles trapezium adds equal non-parallel sides, equal angles at each base and equal diagonals. A right trapezium has two right angles along one non-parallel side. The extra marks or stated name justify those additional facts; the single parallel pair does not justify them on its own.

Keep a kite’s two diagonal roles distinct

The kites used here have two different-length pairs of adjacent equal sides. In kite PQRS with PQ=PS and RQ=RS, the equal pairs meet at P and R. PR is the symmetry diagonal. The opposite angles at Q and S, lying between unequal side lengths, are equal. The angles at P and R do not have to be equal.

The symmetry diagonal PR meets QS at right angles and bisects QS; it also bisects the angles at P and R. If they meet at T, then QT=TS, but PT=TR is not a general kite property. A diagram with PT=7 cm and TR=3 cm makes the distinction visible: both pieces lie on the same symmetry diagonal, yet need not be equal. Here the symmetry line explains the specific equalities in the kite; a complete line- and rotational-symmetry course is separate.

Check whether all the givens can hold

For a valid marked shape every stated property must fit, not just the total of its interior angles. A four-angle list can add to 360° while contradicting a promised parallel pair. Test the co-interior sums and any extra equality marks before attempting to construct the advertised figure.

If data contradict one another, explain the contradiction on a labelled condition card. Do not draw a distorted “solution” and attach impossible marks to it. For a valid case, sketch the true parallel pair, equal-side pairs and diagonal intersection, then attach each deduction to a named relationship. Use exact stated data rather than measuring the picture; the local naming conventions here do not settle every textbook’s inclusive taxonomy.

Sources for this lesson

Pause and explain

Trapezium ABCD has AB∥DC,A=76°,D=104°,B=83°. Which conclusion is correct?

Put the idea to work

Worked example

Use two separate labelled panels. Panel 1: right trapezium ABCD has AB∥DC,A=D=90°,B=64°. Mark the parallel pair and find C. Panel 2: kite EFGH has EF=EH and FG=GH, with those pair lengths different; E=76°,G=104°. Mark the two adjacent equal-side pairs and find F,H. Keep each angle arc inside its named polygon. In the kite draw its symmetry diagonal EG, mark its equal angle parts at E and G, and calculate those four parts.

Show the worked solution
  1. In panel 1, BC is a transversal between AB and DC. Its co-interior pair B+C totals 180°, so C=180−64=116°.
  2. The panel 1 interiors check as 90+64+116+90=360°. The two right angles belong at A and D; no isosceles condition was supplied.
  3. In panel 2, the equal opposite angles are F and H, because the equal adjacent pairs meet at E and G. They share 360−76−104=180°, so F=H=90°. Check 76+90+104+90=360°.
  4. The kite’s equal adjacent pairs meet at E and G, so EG is its symmetry diagonal and bisects those endpoint angles. Each E part is 76÷2=38°, and each G part is 104÷2=52°. Put the two 38° arcs at E and two 52° arcs at G; these are not the meeting angles of the diagonals.

Answer Panel 1: C=116° by co-interior angles on BC. Panel 2: F=H=90° because those equal opposite kite angles share the remaining 180°. Both full interior totals are 360°. The symmetry diagonal EG bisects E into 38°+38° and G into 52°+52°.

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From guided practice to a new situation

Write your answer and reasoning first. Use a hint only if you are stuck. The model solution is for self-checking; your written work is not automatically marked.

1 · Guided

Panel 1 is isosceles trapezium ABCD with AB∥DC,AD=BC,B=(3x+4)°,C=(5x+16)°. Draw the parallel and equal-leg marks; find x and all four interiors. Panel 2 is a separate kite PQRS with PQ=PS,RQ=RS. Draw PR and QS meeting at T, with PT=7 cm,TR=3 cm,QT=4 cm. Find TS,PR,QS and the meeting angle, and explain why T is not the midpoint of PR. In the isosceles trapezium draw AC and BD: state whether AC=BD and justify the claim from the isosceles condition. Would the same conclusion follow for every general trapezium?

Give me a hint

Name each co-interior or equal-opposite pair before writing an equation; keep both diagrams separate.

Compare my reasoning
  1. In panel 1, B+C=180° gives (3x+4)+(5x+16)=180. Hence 8x+20=180 and x=20, so B=64° and C=116°.
  2. The isosceles condition gives equal base-angle pairs: A=B=64° and D=C=116°. These four angles total 360°.
  3. In panel 2, PR is the symmetry diagonal, so it bisects QS at right angles. Therefore TS=QT=4 cm, QS=8 cm and PR=PT+TR=10 cm.
  4. The meeting angle is 90°, but PT=7 cm differs from TR=3 cm. Thus T is the midpoint of QS, not of PR; kite diagonals do not generally bisect each other.
  5. The equal legs AD=BC establish the isosceles trapezium property that its diagonals are equal, so AC=BD. No numerical diagonal length was supplied. A general trapezium lacks that extra condition, so equal diagonals do not follow automatically from one parallel pair.

x=20; trapezium angles A,B,C,D=64°,64°,116°,116°. In the kite, TS=4 cm,PR=10 cm,QS=8 cm and the diagonals meet at 90°. T does not bisect PR because 7 cm≠3 cm. In the isosceles trapezium AC=BD; equality is not automatic for a general trapezium and no numerical diagonal length is determined.

Look for these in your work

  • Show the trapezium’s actual parallel/equal-leg marks and solve its co-interior equation.
  • Use equal base angles to complete all four labels.
  • Explain the kite’s one-way diagonal bisection and justify AC=BD specifically from the isosceles trapezium condition, without inventing a length.
2 · Independent

Panel 1: general trapezium ABCD has AB∥DC,A=(2x+18)°,D=(4x+6)°,B=74°,C=106°. Find x and all four angles; decide whether it is isosceles. Panel 2: kite PQRS has equal adjacent pairs meeting at P,R, with P=(4u+12)°,R=(2u+18)°,Q=S=(3u+45)°. Draw the named angle arcs and equal-side marks; find u and all four kite interiors. Draw symmetry diagonal PR in the kite and calculate its two endpoint angle parts at P and at R; mark each equal pair.

Give me a hint

Use the parallel pair for x and then the isosceles condition; in the kite ask which diagonal is the symmetry line.

Compare my reasoning
  1. For panel 1, A+D=180° gives (2x+18)+(4x+6)=180, hence 6x+24=180 and x=26. Therefore A=70° and D=110°.
  2. Together with B=74°,C=106°, both co-interior pairs total 180° and the four interiors total 360°. A and B are unequal, so the trapezium is not isosceles.
  3. For panel 2, add the four interiors: (4u+12)+(2u+18)+2(3u+45)=360. Thus 12u+120=360 and u=20.
  4. The kite angles are P=92°,Q=105°,R=58°,S=105°. The equal pair is Q,S, not P,R; all four total 360°.
  5. PR bisects the angles at the vertices where the equal adjacent pairs meet. Hence each P part is 92÷2=46° and each R part is 58÷2=29°. This local symmetry-diagonal use is distinct from assuming P=R or that both diagonals are bisected.

x=26; trapezium angles A,B,C,D=70°,74°,106°,110°, so it is not isosceles. u=20; kite angles P,Q,R,S=92°,105°,58°,105°, with Q=S the equal opposite pair. PR divides P into 46°+46° and R into 29°+29°.

Look for these in your work

  • Solve and check both x and u equations.
  • Label all four angles in each separate diagram.
  • Identify Q=S and mark the PR endpoint bisections as 46° at P and 29° at R, while explaining why the trapezium is not isosceles.
3 · Transfer

A supplier’s condition card claims trapezium ABCD has AB∥DC and interiors A=85°,B=95°,C=105°,D=75°. Check whether such a marked shape can exist; do not draw a supposedly valid outline before checking. Separately draw a valid kite PQRS with PQ=PS,RQ=RS and different pair lengths, P=110°,R=70°. Find Q,S and state which diagonal is bisected, with a reason. Mark the equal parts made by symmetry diagonal PR at P and R, and calculate them.

Give me a hint

A total of 360° is necessary but not sufficient for a marked trapezium. Check each non-parallel transversal as well.

Compare my reasoning
  1. The proposed trapezium angles total 85+95+105+75=360°. That passes only the general quadrilateral check.
  2. AB∥DC also requires A+D=180° and B+C=180°. The proposed sums are 160° and 200°, which contradict both co-interior requirements. Reject the advertised marked trapezium.
  3. In the separate valid kite, the equal opposite pair Q,S shares 360−110−70=180°, so Q=S=90°.
  4. The equal adjacent pairs meet at P,R, so PR is the symmetry diagonal and bisects QS at right angles. PR itself need not be bisected. Keep this valid diagram separate from the rejected condition card.
  5. PR bisects its endpoint angles, giving 110÷2=55° at each P part and 70÷2=35° at each R part. Those vertex-angle bisections are separate from PR bisecting QS and do not imply PR itself is bisected.

The advertised trapezium is impossible: its total is 360°, but the required co-interior sums are 160° and 200° instead of 180°. In the valid kite Q=S=90°; PR bisects QS perpendicularly, while PR is not generally bisected. PR divides P into 55°+55° and R into 35°+35°.

Look for these in your work

  • Check all advertised parallel-angle conditions and state the contradiction.
  • Keep the impossible condition card separate from the valid kite diagram.
  • State which diagonal is bisected, and justify the endpoint half-angles 55° and 35° with correctly placed arcs.

Common mistakes

  • Applying equal base angles or equal diagonals to every trapezium.
  • Assuming both kite diagonals are bisected or choosing the wrong equal opposite-angle pair.
  • Accepting impossible marked data merely because the four angles add to 360°.
Recall without your notes

What can you explain now?

Kite ABCD has AB=AD and CB=CD, with the two adjacent-pair lengths different. Its diagonals meet at O. Which diagonal is bisected, and is AO=OC guaranteed?

Compare with the explanation

AC bisects BD, so BO=OD. AO=OC is not guaranteed.

The equal pairs meet at A,C, making AC the symmetry diagonal. It perpendicularly bisects the other diagonal BD; the reverse bisection is not a general kite property.

After trying it yourself, choose your next review. This is your self-assessment.

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Make it stick

Sketch a general trapezium and an isosceles trapezium with their justified marks. Then sketch a kite and explain its equal opposite angles and the different roles of its two diagonals. Describe why an angle-total check alone can miss impossible data.

If you needed the solution, close it and solve the problem again from a blank page. A correct answer is stronger when you can explain the reason for each step.

Keep learning Mathematics A

Course scope and assessment

Linked teaching: sections 1.1 to 1.11, 2.1 to 2.8, 3.1 to 3.4,4.1–4.11 and5.1–5.2 and6.1–6.3; 2.5, 3.2,3.4 and5.1 are Higher only. This includes Foundation content inherited by Higher and Higher extensions for recurring decimals, surds, fractional powers, algebraic sets, Venn counts, repeated percentage changes, calculations with measurement bounds and standard-form application problems. Algebra includes Foundation symbols, integer index laws, substitution, like terms, brackets and monic factorisation, plus Higher fractional indices, multiple brackets, non-monic factorisation, algebraic fraction operations with domain restrictions, completing the square and proofs. Formulae include derivation from words and diagrams, substitution, single-occurrence subject changes including squares and roots, and Higher repeated-subject and harder power/root rearrangements. Linear equations cover both sides, brackets, fractional coefficients and constructing models from data. Section 2.5 adds all eight direct/inverse x, square, cube and square-root proportion families with actual graph exploration and domain checks. Section 2.6 adds shared elimination and substitution, exact fractions, contextual feasibility and repeated or inconsistent conditions; the additional Higher graphical lesson interprets genuine-line intersections, vertical lines and off-screen crossings. Section 2.7 adds Foundation monic quadratic factorisation, with Higher general factorisation, quadratic-formula and completing-square alternatives, context derivation and line–parabola/line–circle systems including full branches and exact paired solutions. Section 2.8 adds required open/closed number-line intervals, linear and compound solving, construction and identification of Cartesian regions, and Higher quadratic sign intervals and harder linear regions. Its Cartesian boundary-drawing convention note does not remove number-line endpoint requirements. Section 3.1 adds term-to-term and position-to-term generation, integer continuation and linear nth terms, plus Higher arithmetic a,d recovery, the general nth-term formula and finite arithmetic sums. Section 3.2 adds Higher-only mappings, both function notations, actual domain/range reasoning, composition in Pearson order with original restrictions, and affine/rational/restricted-branch inverses. Section 3.3 has nine shared coordinate, straight-line, travel, speed, conversion and quadratic-plotting lessons, followed by two additional Higher line-equation lessons, four Higher graph-family lessons, nine transformation/equation-recovery lessons and three drawn-tangent/intersection lessons. All nine Foundation source rows have lesson links, with paired interpretation and linear/quadratic plotting breadth guards. The broad additional Higher H3.3A row requires integer polynomial/cubic, sparse mixed reciprocal, degree sine/cosine and degree tangent lessons with every practice stage. H3.3B requires all four transformation forms across linear, quadratic, degree sine and degree cosine functions in eight core lessons; H3.3C also requires their algebra recovery and the ninth domain/equivalence/order synthesis lesson. H3.3D requires drawn-tangent construction and signed rise/run using actual units; calculus is not a replacement. H3.3E requires both line/quadratic and genuine line/cubic intersections and their nonlinear-minus-linear difference graphs, with all practice stages. All sixteen Graphs source rows now have teaching and staged-practice links; exhaustive subskill approval, mastery and assessment readiness remain unestablished. Section 3.4 adds six Higher-only lessons for variable rates, integer-power differentiation, gradient/rate conditions, stationary coordinates classified by original graph shape, one-dimensional motion and other practical models. H3.4C requires gradient and stationary slices; H3.4E requires both motion and other-practical slices. Preserve original domains, negative-power exclusions, admissible counts and boundary candidates. All five source rows have structural links, not exhaustive subskill approval or specialist/assessment validation. Section4.1 adds six shared Foundation/inherited-Higher lessons for selected acute/right/obtuse/reflex arcs, point/straight/intersection and parallel-transversal angles, triangle sums/exteriors, isosceles/equilateral and right/mixed triangles. All four shared rows have structural links; B requires both local and parallel strands and D both special and right-triangle strands, each with every practice stage. No additional H4.1 rows are invented. Preserve labelled geometry and reasons, the auxiliary-parallel triangle-sum argument, actual straight extensions, inclusive equilateral/isosceles and right-isosceles categories, and impossible/insufficient-data checks. Section4.5 constructions,4.4 measurement/bearings and the full H4.7 reasoning scope remain separate, without a blanket formal-proof waiver. Section4.2 adds seven shared Foundation/inherited-Higher Polygons lessons for all nine named polygon examples, convex/concave quadrilateral sums, all six named quadrilateral property families, general/regular polygon angles and congruence correspondence. Its seven rows A–G have structural links, with no additional Higher rows; C requires both family lessons and every practice stage. F/G remain two distinct published IDs supported by the same congruence lesson. Rhombus/square and kite endpoint-angle bisection and isosceles-trapezium equal diagonals are conservative standard-property breadth, not invented verbatim source bullets. Preserve reflex interiors, valid internal triangulations, local trapezium/kite conventions, exact integer side counts and impossible-data guards. Section4.3 symmetry,4.5 formal constructions,4.11 similarity and the full H4.7A reasoning programme remain separate. Literal book tags omit A; G has no Hub tag, and the Book2 map/proof congruence location and chapter7 page-range conflict remain unresolved. Section4.3 adds three shared Foundation/inherited-Higher Symmetry lessons for the one F4.3A source row, requiring every lesson and practice stage for the joint line/rotation capabilities. Draw all mirror lines, test a fixed original against a separate tracing about a chosen centre, count identity once and distinguish order1 from a blank circle’s non-finite rotations. Preserve indentations and true physical disk/colour features; the chosen missing-vertex parallelogram completion is original breadth, not an extra row or4.5construction credit. No additional H4.3 row is invented. The sole literal book link is Book2 Shape and Space6; no Book1 tag or explicit4.3Hub tag is invented, and its mapped chapter body/full final-book alignment remains unverified. Section4.5construction,5.2transformations,4.11similarity and full Higher reasoning remain separate. Section4.4 adds eight shared Foundation/inherited-Higher Measures lessons for seven A–G source rows and no additional Higher rows. Use complete instrument-scale, time-interval, sensible-estimate, nearest-degree protractor and three-figure-bearing teaching. F4.4F requires the full speed lesson; broad F4.4G requires speed, density and pressure, each with its worked explanation and every practice stage, with source binding on the same complete record. Preserve calibrated ticks and actual instrument action, compatible units, midnight/day order, approximate readings and north conventions. Keep numerical references hidden until calibrated attempts. Time recovery requires positive speed; at zero speed positive distance is impossible and zero distance alone is underdetermined. Density uses positive volume, displacement differences and explicit additive-volume assumptions; pressure uses the given formula, supplied forces and positive contact areas. Literal book navigation names only D and G; no A/B/C/E/F tags are invented, and Book1 map255–268/proof256–269 remains unresolved. These structural links do not complete4.5 instrument/compass constructions or scale drawings,5.2 transformations or formal assessment. Section4.5 adds six shared Foundation/inherited-Higher Construction lessons for four A–D rows and no additional Higher rows. A requires both nearest-millimetre measurement and actual line drawing. BroadB requires complete triangles and other two-dimensional shapes; broadD requires both straight-edge-and-compasses bisectors. Source binding and complete teaching/worked/all three practice stages must belong to the same required record. Use real ruler, protractor and compass action with retained construction evidence, physical calibration and honest approximate readings. Keep private endpoint readings, pose coordinates, solved vertices/crossings and reference directions hidden before instrument attempts. Respect valid mirror branches and selected minor/reflex angles; reject impossible triangles, insufficient data and degenerate crossings. Scale drawings require construction before measuring the unknown, compatible units and a labelled positive scale; drawing placement offsets remain givens. Literal book navigation names B/C/D only in Book2 Shape and Space6 with Hubs37/36/38. A has no literal chapter/Hub tag and no Book1 tag is invented. Public proof contents agree with map128–160 and show generic Constructions139, but the relevant body, full-book/Hub content and exact subtype pages remain unavailable. These structural links do not grant4.6 circle properties,4.7 whole geometrical reasoning,4.8 trigonometry,4.9 mensuration,4.11 maps/similarity,5.2 transformations or loci credit. The nearby circle formal-proof note is not imported. Section4.6 adds nine original Circle properties lessons for two shared Foundation and three additional Higher rows. The first three shared lessons cover all nine named parts, both chord/centre implications and both tangent facts. F4.6B requires both chord and tangent lessons. Additional Higher H4.6A requires both internal-chord and external-secant products with original named lengths, positive lengths and correct internal/near-far point order. H4.6B requires actual concyclic boundary vertices. H4.6C requires all five theorem parts across centre/circumference, diameter/same-segment, cyclic-opposite-angle and alternate-segment lessons. Every required slice needs substantive teaching, explained worked work and all three practice stages on one source-bound record; no half-row or untagged duplicate closes the bundle. Keep given marks separate from derived marks and retain selected major/minor arcs, tangent rays and physical algebraic-root domains. The no-formal-proof note belongs to H4.6C, not a blanket H4.6A/H4.7 exemption. Literal Book2 chapter5 tags F4.6B/H4.6B/H4.6C and chapter8 tags H4.6A/H4.6C are navigation only; no F4.6A or Book1 tag is invented. Chapter8 map326–349 versus proof chapter-start325 and next chapter349 remains unresolved; relevant final bodies and Hub content are unverified. These structural links do not complete construction, whole geometrical reasoning, trigonometry or mensuration, or establish specialist approval, mastery or formal assessment. Section4.7 adds five original Geometrical reasoning lessons for one shared F4.7A and one additional H4.7A row. The shared row jointly requires line/triangle, polygon and chord/tangent numerical reasoning, including lengths; the Higher row jointly requires both circle and mixed-angle standard-statement chains. Every required record needs substantive teaching, its explained worked example and all three fresh practice stages, with the source ID on that same complete record. Preserve actual diagram hypotheses, common arcs, contact radii, selected tangent rays, cyclic/straight point order, valid internal triangulations and the unknown regular-polygon outline after deduction. Each geometric equation needs a named reason; a correct number or sufficient text length does not validate an arbitrary written argument. The H4.6C formal-theorem-proof note remains local, not a blanket4.7 waiver. Only literal H4.7A Book1 Shape and Space1/Hub89,137,138,139 navigation is used; no Foundation4.7A or Book2 tag is invented. Public Book1 chapter60–99 is available but does not establish full Higher circle-angle or Hub body scope. These links do not award4.5construction skill, specialist approval, mastery or formal assessment. Section4.8 adds eleven original Trigonometry and Pythagoras’ theorem lessons for three shared F4.8A–C and six additional H4.8A–F rows. The first four are shared; the last seven are additional Higher. F4.8B jointly requires lengths with all acute ratios and inverse-angle work; H4.8C jointly requires sine-rule and cosine-rule teaching. Every row needs all its named source-bound records, substantive teaching, explained worked work and every Guided/Independent/Transfer stage. Preserve both missing-leg and missing-hypotenuse Pythagoras, signed bearing components with local north, all three obtuse functions, actual elevation/depression horizontals, admissible SSA branches and included-angle area restrictions. Three-dimensional work requires perpendicular sections and the actual foot/projection for a line-plane angle; plane-plane angles are excluded. Positive physical lengths, inverse domains, triangle inequalities, degree mode, exact forms and final-only rounding remain explicit. Chosen SSA two/one/no and inverse-area comparisons are safeguards, not extra syllabus rows. Literal navigation uses Book1 SS1–4 only: no Book2 tag or dedicated H4.8A Hub is invented. Hub145 is tagged F4.8A in SS1 and H4.8D in SS3; the former title does not extend Foundation into3D. Public Pythagoras body74–76 is available, but SS2/3/4 bodies and Hub content are unverified. SS2 map176–197 versus summary198, and SS3 map243–254 versus proof-start244/summary255 remain unresolved. No4.5construction,4.9mensuration, full-book, specialist, mastery or formal-assessment credit follows from these structural links. Section4.9 adds eight original Mensuration lessons for five shared F4.9A–E and one additional H4.9A row. The first six are shared; the last two are Higher. F4.9E jointly requires complete circle and semicircle/compound-boundary lessons; H4.9A jointly requires degree arcs/perimeters and sector-area/recovery lessons. Every required source-bound record needs substantive teaching, its explained worked example, checks and all Guided/Independent/Transfer stages. Retain both-direction linear/area conversions, exposed polygon boundary traces and internal joins, triangle/rectangle decomposition and contained disjoint cutouts, outside perpendicular heights, both parallelogram/trapezium methods, radius/diameter recovery and semicircle arc-versus-perimeter distinctions. Preserve major/remaining sector sweeps, positive physical roots, inverse dimensions, annular inner arcs and radial gaps, compatible square/linear units and question-specific precision; no universal3sf rule is invented. Radians are excluded; ordinary sector arc-plus-two-radii boundaries require0<θ<360, while a full disk has no radial cuts. Literal Book1 SS1 tags B/C/D/E and HigherA with Hubs47/48/118, plus Number4A/Hub14, are navigation only; no Book2 tag or verified Hub body is inferred. Public SS1contents summary98 versus actual99 and Number4map198–206 versus proof199–207/next208 stay explicit. Chosen compound/inverse/annular safeguards do not add source rows or grant construction, volume, similarity, full-book, specialist, mastery or formal-assessment credit. Section4.10 adds nine original 3D shapes and volume lessons for six shared F4.10A–F rows and one additional H4.10A row. The first seven are shared; the final sphere and right-cone lessons are additional Higher. Teach all seven named solid families, complete face/edge/vertex incidence with hidden features, planar triangle/rectangle surface inventories and cylinder surfaces with actual open/closed conditions. F4.10E requires both complete prism and cylinder-volume slices; H4.10A requires both complete sphere and right-cone surface-and-volume slices. Every required source-bound record needs substantive teaching, worked methods, checks and all Guided/Independent/Transfer stages. Preserve actual face altitudes, positive inverse dimensions, full-length groove conditions, internal capacity and fill levels, contact-patch removal, cubic unit factors and1L=1000cm³. Curved-solid tasks state their flat-face/rim/apex convention without inventing a universal mark-scheme count. Nets, joins, inverse applications and solid hemispheres are chosen breadth, not extra official rows or instrument, frustum, similarity, pyramid-volume or hollow-capacity credit. Keep exact values/π and question-specific precision, including explicit significant trailing zeroes or scientific form. Literal Book2 Shape and Space9 tags C/D/E/F and HigherA are navigation only; no A/B or Book1 tags are inferred. Hubs56/57/55/84/131 do not establish body coverage, and no F4.10F Hub tag is invented. Map359–385 versus proof358–384/next385 remains unresolved; relevant chapter body and full-book/Hub content are unavailable. Specialist, formal-assessment and mastery approval remain pending. Section4.11 adds seven original Similarity lessons for exactly two shared F4.11A/B rows and three additional H4.11A/B/C rows. The first four are shared correspondence, forward/inverse lengths, maps and plans; the final three cover area factors, volume factors and mixed problems. F4.11A requires both complete correspondence and length slices, and F4.11B requires both map and plan slices, with source binding, substantive teaching, worked methods, checks and every explained Guided/Independent/Transfer stage in the same actual record. Retain matching angles and every corresponding side, concave reflex corners, positive factors, inverse recovery, parallel/shared-vertex hypotheses, whole/part order, compatible units, route versus direct distance, and uniform print-resizing scale recovery. Higher work distinguishes k, k² and k³, positive roots, similarity hypotheses, unit powers, actual closed-cuboid total surfaces, physical dimensions, exact money before rounding, and parallel-section cone subtraction as a chosen application. No extra official row, transformations, instrument calibration, formal construction or general frustum-formula credit is claimed. Literal Book2 Shape and Space6 F4.11B/Hub36, Shape and Space7 F4.11A/Hub85, and Shape and Space9 H4.11A/B/C with Hubs143/144 are navigation only, with no Book1 tag invented. Shape and Space6 map128–160/proof128/summary159/next161, Shape and Space7 map223–248/proof222/summary247/next248, and Shape and Space9 map359–385/proof358/summary384/next385 remain explicit. The actual proof places Similar shapes at147 under Shape and Space6 while the literal F4.11A map tag remains under Shape and Space7; this topic-location conflict is unresolved. Relevant chapter and Hub bodies are unavailable; no full-book, specialist, formal-assessment or mastery approval follows. Section5.1 adds nine original additional Higher Vectors lessons for exactly H5.1A–G and no shared Foundation rows. All required source-bound notation, scalar, arithmetic, magnitude, route, position/division, parallel/collinear, simple-proof and intersection strands need substantive original teaching, an explained worked example and exactly one complete Guided/Independent/Transfer task in the same record. Preserve directed endpoints, signed/scalar and zero-vector exceptions, exact fractions and radicals, final-only rounding, current own head-to-tail joins, one-origin positions, t=0/t=1 endpoints and external points without clamping. Geometric conclusions require actual nonzero, nonparallel, noncollinear or simple-boundary hypotheses; formal two-to-four-symbol planar identities do not assert an independent spatial basis. H5.1G requires genuine explained geometric proof, not numerical resemblance or unchecked text. The H4.6C local theorem-proof note is not a blanket vector-proof waiver. Literal Book2 Shape and Space10 H5.1A–G map427–450/proof426/summary449/next450 remains unresolved; Hub167 covers A/B/C/D/F,168 A/E and169 G. Navigation does not establish modular equivalence. No Book1 tag or unseen Vectors chapter/Hub body is invented: the public uncorrected2025proof exposes contents and Number8 body, not Vectors. November2026/June2027 linear entry and regional-centre limits remain separate. Full-book, specialist, mastery and formal-assessment approval remain pending. Section5.2 adds twelve original shared Transformation geometry lessons across exactly F5.2A–M and no additional Higher row. Full source-bound bundles require substantive teaching, explained worked and exactly one complete Guided/Independent/Transfer task in each record. Retain every labelled corner and corresponding trace, signed/general rotations, complete equivalent mirror lines, common translation columns, rigid distances/angles, positive and fractional factors, supplied/free centres and factor1 identity exceptions. General-degree written3dp is separate from unrounded geometry. Ordered compositions are chosen breadth rather than an extra source row; compare both orders, including commuting perpendicular reflections, and distinguish reverse order from the inverse. Source/book/year and proof/physical-construction limits remain explicit. Graphical representation6.1 adds ten original lessons: six shared Foundation tabulation/two-way/pictogram/bar/pie/interpretation slices and four additional Higher histogram construction/reading and cumulative construction/use slices. Each complete source-bound record and every practice stage are required; tables or diagram names alone do not establish actual construction. Keep scales/units/keys, zero categories, unequal continuous widths and density/area, hidden missing calibration and pie labels, uniform partial-class estimates, cumulative boundaries and nonunique flat inverses. No Statistical measures6.2 or Probability6.3 credit follows. Literal book/Hub metadata is navigation only: Book2 Handling Data4 F6.1Aii is a modular subpart; Book1 Handling Data3 map398 starts differently from proof397 and Book2 Handling Data6 map208 from proof207. Relevant chapter/Hub bodies remain unavailable. Statistical measures6.2 adds eight original lessons: four shared Foundation list/frequency averages, simple mean problems and grouped midpoint estimates/modal classes; four additional Higher spread, discrete quartiles, median and IQR from cumulative diagrams. Every source-bound record needs substantive teaching, its explained worked example and all three unique practice stages. Preserve repeated positions, weighted counts, observed zero-frequency extremes, compatible units, grouped estimation limits, the explicitly chosen median-of-halves convention, actual graph guides, each curve’s own total and nonunique plateau intervals. Literal Book2 Handling Data4/5/6 tags and Hubs are navigation metadata only; no Book1 tag, complete chapter body or Hub access is inferred. Handling Data6 map208–222 versus proof207/summary221/next222 stays explicit. Statistical measures alone does not replace Probability6.3 teaching. Probability6.3 adds nine original lessons for ten shared F6.3A–J and four additional H6.3A–D rows. The first five are shared language/scales/models, complete single/two-event sample spaces, Venn probabilities, experimental estimates/expected frequencies and complement/mutually-exclusive addition; the final four are Higher independent trees, actual without-replacement trees, simple conditioning and contextual inverse/mixed models. Each required source-bound strand needs substantive teaching, an explained worked example and exactly one complete Guided/Independent/Transfer task in the same actual record. F6.3C requires both model and sample-space slices; H6.3A requires independent, dependent and application trees; H6.3B requires independent and application slices; H6.3C requires without-replacement, simple-conditioning and application slices; H6.3D requires conditioning and application slices. Retain physical identities, nonuniform weights, original ordered histories, complete branches/terminal events, unchanged versus changing contents, restricted positive conditional denominators and undefined empty conditioning. Experimental variability and fractional expected counts are model predictions rather than guaranteed observations. Inverse physical counts keep original nonnegative integer/positive-total domains. Chosen three-set, three-stage and inverse safeguards do not add source rows or a named general conditional theorem. Literal Book1 HandlingData1/2/3 tags and Hubs are navigation only; no Book2 tag or unseen probability chapter/Hub body is invented. Preserve map228–242/proof229–243/next244, map303/proof304–328/next329 and map398–428/proof397/summary426/next428; missing explicit Hub A/B/F/J tags remain absent. The common two-coin elementary model is not claimed as novel. All39 source sections and242 requirements now have structural teaching/practice links; that is not exhaustive subskill, teacher, full-book, mastery, specialist or formal-assessment approval. The independent source inventory contains 162 Foundation requirements and 80 additional Higher requirements; some lettered requirements contain multiple skills. A lesson link alone does not verify every skill or examination readiness. Written practice is self-checked, not automatically marked. Specialist approval and cumulative assessment have not been established. This course follows the linked Issue 2 linear 4MA1 specification. The 2026/2027 entry manual lists F/H in November 2026 and June 2027; regional FR/HR entries are June 2027 only and depend on centre eligibility. Modular 4XMAF and 4XMAH coverage is separate.

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