The answers are:
x = 13
y = -11
4b - 7 + 2b + 11 and b + 3 + b + 1 are congruent.
You add the common factors in each problem: 2b + 4 = 2b + 4
Vertex angle = x
1 base angle = 1/2x - 8
180-x = (1/2x-8)x2
180-x = x-16
196-x = x
196 = 2x
x=98
If you want explanation please ask me .