The figure is not drawn to scale. Triangle TUS is an isosceles triangle. Triangle QRS is an equilateral triangle. ∠UST is
15 of ∠RQS and ∠RSU = ∠QST.
- Find ∠RSU.
- Find ∠QTS.
(a)
∠RSQ = 60° (Equilateral triangle)
∠UST
= ∠RSQ x
15 = 60° x
15 = 12°
∠RSU = ∠QST
∠RSU
= ∠RSQ - ∠USA) ÷ 2
= (60° - 12°) ÷ 2
= 48° ÷ 2
= 24° (Isosceles triangle)
(b)
∠QTS
= 180° - ∠RQS - ∠RSU
= 180° - 60° - 24°
= 96° (Angles sum of triangle)
Answer(s): (a) 24°; (b) 96°