Answer:
x = 7
Explanation:
Since the lines are parallel, we know that the two angles are equal. So you can write (7x - 4) = (5x + 10). Then you just solve for x.
7x - 4 = 5x + 10
add 4 from both sides to get
7x = 5x + 14
subtract 5x from both sides to get
2x = 14
divide both sides by 2 to get
x = 7