PSLEIn the figure, LMNP is a straight line, MPQR is a parallelogram and QN = QR. ∠RLM is a right angle, ∠LRM = 38° and ∠PQN = 20°.
- Find ∠s.
- Find ∠t.
(a)
∠RLM = 90° (Right angle)
∠s
= 90° + 38°
= 128° (Exterior angle of a triangle)
(b)
∠PQR = ∠PMR = 128° (Parallelogram)
∠NQR
= 128° - 20°
= 108°
∠t
= (180° - 108°) ÷ 2
= 36° (Isosceles triangle)
Answer(s): (a) 128°; (b) 36°