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Complete the congruence proof

Thinking deductively to determine whether triangles are congruent is a challenging process for many students. The additional requirement of writing up the proof in the formal language of geometry can be overwhelming. 

You can download the Proving congruence: Student worksheet which allows your students to gradually gain experience in the form and language of a deductive proof. The early questions provide the framework needed to write a logical and accurate proof. This allows students to become familiar with the new format and builds their confidence.

Gradually, more and more is left to plan and write, until eventually students can write the complete proof without prompts.

You can also download the Proving congruence: Answers.

Curriculum links

Year 10: Apply logical reasoning, including the use of congruence and similarity, to proofs and numerical exercises involving plane shapes.