#### Answer

We can use the SAS theorem to prove the triangles are congruent. From the diagram, we can see that two sides of each triangle are marked congruent. Vertical angles are formed by those congruent sides, and we know that vertical angles are congruent to one another. We have two sides and an included angle congruent in the two triangles, so the SAS theorem applies to this problem.

#### Work Step by Step

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