Work out the value of x.

Answer:
67.5 degrees
Step-by-step explanation:
The angles at the center of the figure = 360 degrees
Therefore, 3x + x + 90 degrees = 360 degrees
simplifying:
4x + 90 degrees = 360 degrees
4x = 360 - 90
4x = 270 degrees
x = 270÷ 4
x = 67.5 degrees