GCSE Maths Practice: congruence-and-similarity

Question 3 of 10

This question tests knowledge of triangle congruence criteria. Knowing these methods is essential for proving triangles are identical in shape and size.

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\( \begin{array}{l}\text{How many criteria are there to prove that two triangles are congruent?}\end{array} \)

Choose one option:

Remember SSS, SAS, ASA, RHS. AAA is similarity, not congruence.

Triangles are congruent if all sides and angles correspond exactly. There are four main criteria used in GCSE geometry: SSS (all sides equal), SAS (two sides and included angle equal), ASA (two angles and included side equal), and RHS (right-angle, hypotenuse, side). Understanding these rules allows students to solve geometric proofs and identify congruent triangles in diagrams. Each criterion has specific applications: SSS for full side comparison, SAS and ASA when combining sides and angles, and RHS only for right-angled triangles. Mastering these ensures students can tackle congruence problems accurately. Avoid confusing similarity (AAA) with congruence: similarity preserves angles but not necessarily side lengths. Practicing with diagrams enhances visual understanding.