Junior Cycle · Geometry Lesson 12 of 12

JCHL Geometry 8: Proof of Theorem 4 (Practise)

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Learning work

You do NOT need to learn these proofs off for the new Junior Cycle — they are for understanding proofs
Every proof has five headings: Diagram, Given, To Prove, Construction, Proof
Theorem 4: draw a line through one corner parallel to the opposite side
Use the straight angle = 180° (axiom) and alternate angles to finish

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