Similar shapes (Edexcel GCSE Maths): Flashcards

Same shape, different sizes

Always equal

In the same ratio (proportional)

All three angles equal

Only 2 (3rd auto equal, angles sum 180°)

All three sides in same ratio

Two sides proportional + equal included angle

Angle between the two sides being compared

Ratio between corresponding sides

Set up proportional ratios and solve

Still maintain angle and ratio relationships

Cross multiply: $a = \frac{c \times b}{d}$