Question

What is the value of x?

Answer 1

Well, 180 - 126 = 54
54 + 58 + x = 180
112 + x = 180
-112          -112
x = 68

Answer 2

We know, Exterior angle is equal to the sum of opposite interior angles.
So, x + 58 = 126
x = 126 - 58
x = 68

In short, Your Answer would be Option A

Hope this helps!