PSLE Joelle has a triangular piece of paper STU with TS = TU, ∠STU = 84° and ∠UVV = 68°. SVU and TVU are straight lines. She folded it along the line VW as shown.
- Find ∠x.
- Find ∠y.
(a)
Length of ST = Length of TU
Triangle STU is an isosceles triangle.
∠TUS
= (180° - 84°) ÷ 2
= 96° ÷ 2
= 48° (Isosceles triangle)
∠x
= 180° - 68° - 48°
= 64° (Angles sum of triangle)
(b)
∠TSU = ∠TUS = 48°
∠z
= 180° - 68° - 68°
= 44° (Angles on a straight line)
∠y
= 180° - 48° - 44°
= 88° (Angles sum of triangle)
Answer(s): (a) 64°; (b) 88°