If you review your parallel lines and vertical angles, you'll discover that A and B have to be equal.
So 8x + 6 = 4x + 38 .
Subtract 6 from each side;
8x = 4x + 32
Subtract 4x from each side:
4x = 32
Divide each side by 4 :
X = 8
Angle B is 4x + 38. That's 70 degrees.
Angle A is 8x + 6. That's 70 degrees too.