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PPT lesson summary · Foundation PPT · CIE Core

Polygons PPT lesson summary

Polygons PPT lesson — Foundation (CIE Core). These slides walk a lower-secondary class through the key ideas with diagrams and worked examples on screen. This page summarises the teaching points for search and revision; download the PowerPoint for the full lesson, and use the companion worksheet and answers PDFs for independent practice.

Download Polygons PowerPointOpen Learning Sheet — PolygonsDownload Polygons answers PDF

Files: foundation-slides-01M65S7GJQTB4G1J1ER650MXJQ.pptx · foundation-25 Polygons handout.pdf · foundation-25 Polygons handout answers.pdf · free public downloads · diagrams on the slides

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}.

Full slides and practice PDFs

This page is a short, searchable overview of the PPT lesson for revision and search engines. Download the PowerPoint for classroom teaching, then use the companion worksheet and answers when available.

PowerPoint / slidesOpen Learning SheetAnswers PDF
WorksheetsTopic summariesTopic videos