Question

select the correct answer. in the given diagram, m || n. prove ∠1 ≅ ∠5. which statement is missing in the proof? o a. ∠3 ≅ ∠7 o b. m∠5 + m∠7 = 180° o c. ∠7 ≅ ∠5 o d. ∠1 ≅ ∠6

Explanation:

Step1: Analyze the proof structure

We know we need to get from $\angle1\cong\angle7$ (by alternate - exterior angles theorem) to $\angle1\cong\angle5$ using the transitive property of congruence. So we need a statement that shows $\angle7\cong\angle5$.

Step2: Recall vertical - angles theorem

Vertical angles are congruent. $\angle7$ and $\angle5$ are vertical angles.

Answer:

C. $\angle7\cong\angle5$