PSLE FGHJ and GJKL are rhombuses. HMJ is a straight line.
- Find ∠JGM.
- Find ∠HJK.
(a)
∠GJH
= (180° - 104°) ÷2
= 76° ÷ 2
= 38° (Isosceles triangle)
∠JGM
= 180° - 124° - 38°
= 18° (Angles sum of triangle)
(b)
∠GLK
= 360° - 280°
= 80° (Angles at a point)
∠GJK = ∠GLK = 80° (Rhombus)
∠HJK
= 80° - 38°
= 42°
Answer(s): (a) 18°; (b) 42°