Learning pack · Foundation · CIE Core

Angles

What's in this pack: printable worksheet PDF, matching answers PDF, and slides (Foundation · CIE Core depth). Angles 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.

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.

📝 Open Learning Sheet ✅ Open answers 🎬 More topic videos (6)📖 Full summary

Lesson slides · narrated video available

Download slides

Files: foundation-2 Angles handout.pdf · foundation-2 Angles handout answers.pdf

Full topic summary

Angles 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.

Key learning points

Angles on a straight line sum to $180^\circ$ ; around a point to $360^\circ$ .
Vertically opposite angles are equal.
In a triangle, interior angles sum to $180^\circ$ ; exterior angle equals the sum of the two remote interiors.
Parallel lines: corresponding equal, alternate equal, co-interior sum to $180^\circ$ .

Worked example 1 — Straight line

Angles on a straight line: $x$ and $65^\circ$ . Find $x$ .

Working

x=180-65=115

Sum to $180^\circ$ .

Worked example 2 — Around a point

Angles $x$ , $90^\circ$ , $120^\circ$ around a point. Find $x$ .

Working

x=360-90-120=150

Sum to $360^\circ$ .

Worked example 3 — Triangle sum

Triangle angles $50^\circ$ , $60^\circ$ , $x$ . Find $x$ .

Working

x=70

Sum to $180^\circ$ .

Worked example 4 — Parallel lines

Alternate angle to $72^\circ$ is $x$ . Find $x$ .

Working

x=72

Alternate angles are equal.

🎬 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 Angles PPT lesson summary.