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PPT lesson summary · Foundation PPT · CIE Core

Similar Shapes PPT lesson summary

Similar Shapes 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.

Files: foundation-slides-01M65P9H6B4BN23349EYH0DBPR.pptx · foundation-14 Similar Shapes handout.pdf · foundation-14 Similar Shapes handout answers.pdf · free public downloads · diagrams on the slides

Key learning points

  • Matching angles are equal; corresponding sides share one scale factor kk.
  • Find kk by dividing a known image side by the matching object side.
  • Missing length = matching length × scale factor (or ÷ if going the other way).
  • Similar does not mean congruent — sizes may differ.

Worked example 1 — Missing side

Scale factor 33; short side 44. Matching side?

Working

1212

Multiply corresponding lengths.

Worked example 2 — Area scale factor

Length scale factor 33. Area SF?

Working

99

Square the length SF.

Worked example 3 — Volume scale factor

Length scale factor 22. Volume SF?

Working

88

Cube the length SF.

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.

Similar Shapes PPT lesson summary — PowerPoint lesson