In the figure, CFJM is a rectangle, JKMN is a rhombus and FGHJ is a parallelogram. ∠JKM = 78° and ∠HJK = 93°.
- Find ∠EJF
- Find ∠JHG
(a)
∠MNJ = ∠MKJ = 78°
∠NJM
= (180° - 78°) ÷ 2
= 102° ÷ 2
= 51° (Isosceles triangle)
∠EJF
= 90° - 51°
= 39°
(b)
∠FJH
= 360° - 93° - 90° - 51°
= 126° (Angles at a point)
∠GHJ
= 180° - 126°
= 54° (Interior Angles, FJ//GF)
Answer(s): (a) 39°; (b) 54°