Answer:
16
Explanation:
You have to know which theorem applies. This theorem only works because we know line m and line n are parallel.
Alternate Exterior Angles theorem says 111 degrees and 7x-1 are congruent.
This means we can set them equal to each other:
7x - 1 = 111
Solve for x:
7x = 112
112 / 7 = x
x = 16