Answer :
EXPLANATION
Applying the Trapezoid Theorem, give us the following relationship:
2*63+ 2*(6x+9) = 360
This is because we have two pairs of congruent angles. Also, the sum of interior angles is equal to 360 degrees.
Applying the distributive property and multiplying numbers:
126 + 12x + 18 = 360
Adding like numbers:
144 + 12x = 360
Subtracting 144 to both sides:
12x = 360 - 144
Subtracting numbers:
12x = 216
Dividing both sides by 12:
x = 216/12
Simplifying:
x = 18
The value of x is 18 units