In the diagram above, |PQ| = |QR|, |PS| = |RS|, ∠PSR = 30o and ∠PQR...

In the diagram above, |PQ| = |QR|, |PS| = |RS|, ∠PSR = 30^o and ∠PQR = 80^o. Find ∠SPQ.

The correct answer is: B

Join PR
QRP = QPR
= 180 - 80 = ¹⁰⁰/₂₀ = 50^o
SRP = SPR
= 180 - 30 = ¹⁵⁰/₂ = 75^o
∴ SPQ = SPR - QPR
= 75 - 50 = 25^o