Answer:
x = 18
Explanation:
Find the diagram attached
If W and X are the endpoints of a diameter on the circle, this means that arc WX is 180degres
Since the angle at the vertex is half the angle at the intercepted arcs.
<V = 1/2(arcWX)
4x+18 = 1/2*180
4x+18 = 90
4x = 90-18
4x = 72
x = 72/4
x = 18
Hence the value of x is 18