QRST is a quadrilateral and OQTS is a trapezium in which OQ // TS and ∠RQT = 112°, ∠QTS = 120°, ∠RST = 68° and TS = TQ. Find
- ∠QRO
- ∠TQO
- ∠QST.
(a)
∠QRO
= 360° - 120° -112° - 68°
= 60° (Sum of angles in a quadrilateral)
(b)
∠TQO
= 180° - 120°
= 60° (Interior angles, QO//TC)
(c)
∠QST
= (180° - 120°) ÷ 2
= 60 ÷ 2
= 30° (Isosceles triangle)
Answer(s): (a) 60°; (b) 60°; (c) 30°