PSLERSTU is a parallelogram, RTV is an equilateral triangle and TU = UV.
- Find ∠RTU.
- Find ∠TUR.
- Find ∠VRS.
(a)
TU = UV
Triangle TUV is an isosceles triangle.
∠UTV
= (180° - 144°) ÷ 2
= 36° ÷ 2
= 18° (Isosceles triangle)
∠RTU
= 60° - 18°
= 42° (Equilateral triangle)
(b)
∠RVU
= 60° - 18°
= 42° (Equilateral triangle)
∠RUV
= 180° - 42° - 18°
= 120° (Angles sum of triangle)
∠RUT
= 360° - 144° - 120°
= 96° (Angles at a point)
∠SRT
= ∠RTU
= 42° (Alternate angles)
∠SRV
= 60° + 42°
= 102°
Answer(s): (a) 42°; (b) 96°; (c) 102°