Question 23
Triangles and QuadrilateralsIn the diagram, |SP| = |SR| and ∠PRS = 50°. Calculate ∠PQR.

- A.120°
- B.110°
- C.100°
- D.80°
Show the answer and explanation
Answer: C (100°)
Explanation
Triangle PSR is isosceles, so ∠SPR = 50° and ∠PSR = 180° − 100° = 80°. PQRS is cyclic, so ∠PQR = 180° − 80° = 100°.