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Prove theorems using similarity


In the following triangle, ECAE=DBAD.
Below is the proof that EDCB. The proof is divided into two parts, where the title of each part indicates its main purpose.
Complete part B of the proof.

Part A: Prove ACAE=ABAD

Part B: Prove EDCB

8AAReflexive property
similarity (Part A, 8)
1012Measures of corresponding angles of similar triangles are equal. (9)
11EDCBIf a transversal crosses two lines and
angles are congruent, then the lines are parallel. (10)