PSLE GHJK is a trapezium with GH parallel to KJ. GMH and LMK are straight lines and GL = LH. ∠LGK = 91°.
- Find ∠GKM.
- Find ∠HLM.
(a)
∠GKM
= 180° - 91° - 21°
= 68° (Angles sum of triangle)
(b)
∠GMK
= 72° (Alternate angles)
∠HGL
= 72° - 21°
= 51° (Exterior angle of a triangle)
∠HLM
= 180° - 51° - 51° - 21°
= 57° (Angles sum of triangle)
Answer(s): (a) 68°; (b) 57°