WAEC - Mathematics (2001 - No. 36)
In the diagram, PQR is a triangle.|PQ| = |PR|, |PS| = |SQ| and PRS = 50°. What is the size of ∠PSQ?
75o
80o
85o
95o
คำอธิบาย
< PQS = 50° (PQ = PR)
< PQS = < SPQ = 50° (QS = PS)
In triangle PSQ, < PQS + < QPS + < PSQ = 180°
50° + 50° + < PSQ = 180°
< PSQ = 180° - 100° = 80°