The 2 angles are vertical angles, which mean they are equal.
Set the two equations to equal and solve for x:
4x + 7 = 5(x-4)
Use distributive property on the right side:
4x + 7 = 5x -20
Add 20 to each side:
4x +27 = 5x
Subtract 4x from each side:
27 = x
X = 27