PSLEIn the figure, EFGH is a straight line, FHJK is a parallelogram and JG = JK. ∠KEF is a right angle, ∠EKF = 37° and ∠HJG = 19°.
- Find ∠l.
- Find ∠m.
(a)
∠KEF = 90° (Right angle)
∠l
= 90° + 37°
= 127° (Exterior angle of a triangle)
(b)
∠HJK = ∠HFK = 127° (Parallelogram)
∠GJK
= 127° - 19°
= 108°
∠m
= (180° - 108°) ÷ 2
= 36° (Isosceles triangle)
Answer(s): (a) 127°; (b) 36°