PSLEEFGH is a parallelogram, EGJ is an equilateral triangle and GH = HJ.
- Find ∠EGH.
- Find ∠GHE.
- Find ∠JEF.
(a)
GH = HJ
Triangle GHJ is an isosceles triangle.
∠HGJ
= (180° - 130°) ÷ 2
= 50° ÷ 2
= 25° (Isosceles triangle)
∠EGH
= 60° - 25°
= 35° (Equilateral triangle)
(b)
∠EJH
= 60° - 25°
= 35° (Equilateral triangle)
∠EHJ
= 180° - 35° - 25°
= 120° (Angles sum of triangle)
∠EHG
= 360° - 130° - 120°
= 110° (Angles at a point)
∠FEG
= ∠EGH
= 35° (Alternate angles)
∠FEJ
= 60° + 35°
= 95°
Answer(s): (a) 35°; (b) 110°; (c) 95°