In the following figure, , , , and . Find .
Step 1: Find .
The sum of a triangle's angle measures is , so we can find by subtracting and from .
Step 2: Find .
We know that is congruent to because each side of one triangle is congruent to the corresponding side of the other triangle.
Since , is congruent to . They have the same angle measure.
Step 3: Find .
Add and .