Find the value of x. Show all work.

x= -9

Step-by-step explanation:

We are given that two sides are congruent. This means the triangle is isosceles. In an isosceles triangle, base angles are congruent. The unlabeled angle and m<2 would be equal because of this. Since the angles in a triangle sum up to 180, we can write an equation to model the situation:

m<2 + m<2 + 84 = 180

x + 57 + x + 57 + 84 = 180

2x + 198 = 180

2x = -18

x= -9