The figure is not drawn to scale. Triangle TUS is an isosceles triangle. Triangle QRS is an equilateral triangle. ∠UST is
25 of ∠RQS and ∠RSU = ∠QST.
- Find ∠RSU.
- Find ∠QTS.
(a)
∠RSQ = 60° (Equilateral triangle)
∠UST
= ∠RSQ x
25 = 60° x
25 = 24°
∠RSU = ∠QST
∠RSU
= ∠RSQ - ∠USA) ÷ 2
= (60° - 24°) ÷ 2
= 36° ÷ 2
= 18° (Isosceles triangle)
(b)
∠QTS
= 180° - ∠RQS - ∠RSU
= 180° - 60° - 18°
= 102° (Angles sum of triangle)
Answer(s): (a) 18°; (b) 102°