Answer:
10
Step-by-step explanation:
Property : -
When 2 lines intersect, vertically opposite angles are equal.
(5x) and (7x - 20) are vertically opposite angles.
So,
7x - 20 = 5x
Step 1 : Subtract 5x on both sides.
7x - 5x - 20 = 0
2x - 20 = 0
Step 2 : Add 20 on both sides.
2x = 20
Step 3 : Divide 2 on both sides.
x = 20/2
x = 10
Hence,
The value of x is 10.
