Question 41
Circle TheoremsThe diagram is a circle with centre O. PRST are points on the circle. Find the value of ∠PRS.

- A.144°
- B.72°
- C.40°
- D.36°
Show the answer and explanation
Answer: A (144°)
Explanation
∠PTS = x stands on the arc PRS, so x = ½(360° − 8x), giving x = 36°. ∠PRS stands on the arc PTS, so ∠PRS = ½ × 8x = 4 × 36° = 144°.