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Learning pack · IGCSE handout

Polygons

What's in this pack: printable worksheet PDF, matching answers PDF (IGCSE / Secure–Stretch practice). Polygon angle sums and regular-polygon exterior angles are standard: exterior angles of any convex polygon sum to 360∘360^\circ.

Resources at the top · full summary · videos with short notes below.

🎒 Resources in this pack

Jump straight to the printable files, or scroll to the summary and videos.

Scaffolded Learning Sheet — attempt the worksheet, then use the Answers for a full written solution.

Files: 24_polygons_handout.pdf · 24_polygons_handout_answers.pdf

Full topic summary

Polygon angle sums and regular-polygon exterior angles are standard: exterior angles of any convex polygon sum to 360∘360^\circ.

Key learning points

  • Interior sum of an nn-gon: (n−2)×180∘(n-2)\times180^\circ.
  • Regular polygon: each exterior =360∘/n=360^\circ/n; interior =180∘−=180^\circ- exterior.
  • Tessellation links to angles at a point.

Worked example 1 — Interior sum

Sum of interior angles of a hexagon?

Working

(6−2)×180=720∘(6-2)\times180=720^\circ

(n−2)×180∘(n-2)\times180^\circ.

Worked example 2 — Regular hexagon

Each interior angle of a regular hexagon?

Working

exterior=60; interior=120\text{exterior}=60;\ \text{interior}=120

Exteriors sum to 360∘360^\circ.

Worked example 3 — Exterior angle

Regular polygon, exterior 24∘24^\circ. Number of sides?

Working

n=360/24=15n=360/24=15

n=360∘/exteriorn=360^\circ/\text{exterior}.

🎬 Topic videos

  • Pascal's Triangle - Numberphile

    Numberphile · 13 min

    Enrichment / curiosity clip for Lower Secondary (Numberphile-style). Use for hooks, clubs, or stretch — not core exam content.

  • All Triangles are Equilateral - Numberphile

    Numberphile · 5 min

    Enrichment / curiosity clip for Lower Secondary (Numberphile-style). Use for hooks, clubs, or stretch — not core exam content.

  • Triangles have a Magic Highway - Numberphile

    Numberphile · 10 min

    Enrichment / curiosity clip for Lower Secondary (Numberphile-style). Use for hooks, clubs, or stretch — not core exam content.

  • Too Many Triangles - Numberphile

    Numberphile · 8 min

    Enrichment / curiosity clip for Lower Secondary (Numberphile-style). Use for hooks, clubs, or stretch — not core exam content.

  • Squaring the Triangle - Numberphile

    Numberphile · 14 min

    Enrichment / curiosity clip for Lower Secondary (Numberphile-style). Use for hooks, clubs, or stretch — not core exam content.

  • 3 Ways to Draw Squares Inside Triangles - Numberphile

    Numberphile · 9 min

    Enrichment / curiosity clip for Lower Secondary (Numberphile-style). Use for hooks, clubs, or stretch — not core exam content.

More Lower Secondary packs

Browse the hub Learning Packs & Summary, or open the compact Polygons summary.

Polygons — Learning pack