PSLEFGHJ is a parallelogram, FHK is an equilateral triangle and HJ = JK.
- Find ∠FHJ.
- Find ∠HJF.
- Find ∠KFG.
(a)
HJ = JK
Triangle HJK is an isosceles triangle.
∠JHK
= (180° - 130°) ÷ 2
= 50° ÷ 2
= 25° (Isosceles triangle)
∠FHJ
= 60° - 25°
= 35° (Equilateral triangle)
(b)
∠FKJ
= 60° - 25°
= 35° (Equilateral triangle)
∠FJK
= 180° - 35° - 25°
= 120° (Angles sum of triangle)
∠FJH
= 360° - 130° - 120°
= 110° (Angles at a point)
∠GFH
= ∠FHJ
= 35° (Alternate angles)
∠GFK
= 60° + 35°
= 95°
Answer(s): (a) 35°; (b) 110°; (c) 95°
