From the proof, we are given that segment AB is parallel to line DE
The missing statement in Step 5 according to the similarity theorem of a triangle is AC/DC = BC/EC: Option B is correct.
- We are to find the required missing step in the proof.
- According to the given reason in step 5 which is the defintiion of similar triangles.
According to similar triangles, the ratio of the similar sides and angles of both triangles is equal to a constant.
The correct proof based on the definition is to take the ratio of the similar sides of the triangles to give AC/DC = BC/EC
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