Answer:
X = 5°
Step-by-step explanation:
180° on a straight line.
180 - 100 = 80 angle ABC = 80°
angle ACB is vertically opposite to the 60° given
ACB = 60°
180 - 80 - 60 = 7x+5
40 = 7x + 5
7x = 35
X = 5