Answer:
Option B. 49.5 degrees
Step-by-step explanation:
Given that arc QS measures 4x-18
Arc QS is a semicircle and hence subtended angle by semicircle at the centre is 180 degrees.
Use this to find the value of x
4x-18 = 180 degrees
Add 18 to both sides
4x=198
Divide by 4
x =198/4 =49.5
So answer is option B
49.5 degrees
