PSLE QRST and RTUV are rhombuses. SWT is a straight line.
- Find ∠TRW.
- Find ∠STU.
(a)
∠RTS
= (180° - 104°) ÷2
= 76° ÷ 2
= 38° (Isosceles triangle)
∠TRW
= 180° - 128° - 38°
= 14° (Angles sum of triangle)
(b)
∠RVU
= 360° - 299°
= 61° (Angles at a point)
∠RTU = ∠RVU = 61° (Rhombus)
∠STU
= 61° - 38°
= 23°
Answer(s): (a) 14°; (b) 23°