Here I will explain you friend
So we know the exterior angle is 127
I am marking this triangle ABC
So 127+angle B=180( Linear pair)
So angle B = 180-127
Angle B =53
Also in this question it is AB = AC
So it is an isosceles triangle
So angle B = Angle X ( angles opposite to the equal side of the triangle are also equal)
So Answer is x =53
Hope it helps you!
