Solve for x
A. 10 degrees
B. 18 degrees
C. 20 degrees
D. 22.5 degrees

Answer:
10
Step-by-step explanation:
This is a complimentary angle (angles the sums up to 90°)
So,
a + b = 90
4x + 5x = 90
9x = 90
x = 90 ÷ 9
x = 10