Find and .
Step 1: Find .
Since and are congruent, is an isosceles triangle. In any isosceles triangle, the angles opposite to the congruent sides are congruent.
Write an equation to represent the sum of angle measures in . Let represent and , and solve for .
Step 2: Find .
is an equilateral triangle, so all its angle measures are equal. To find the measure of any angle in the triangle, divide the sum of a triangle's angle measures by 3.
To find , add and .