IP EMaths Notes (Upper Sec, Year 3-4): 12) Similarity and Congruency

Q: What does IP EMaths Notes (Upper Sec, Year 3-4): 12) Similarity and Congruency cover?
A: Use similarity ratios and congruency criteria to prove geometric relationships and scale figures accurately.

Similarity compares shapes with proportional sides and equal angles, while congruency proves exact matches. Keep diagrams annotated with tick marks, matching angle symbols, and explicit ratio statements so the reader can follow the logic without guessing.

Keep the full topic roadmap handy via our IP Maths tuition hub so you can jump into related drills, quizzes, or diagnostics as you move through these notes.

Quick reference

• Similarity shortcut: write $\triangle ABC \sim \triangle DEF$ when all corresponding angles match and the three side ratios are equal.
• Triangle similarity criteria:
  • $\text{AAA}$: three angle matches force similarity.
  • $\text{SAS}$