In the figure, ZCFJ is a rectangle, FGJK is a rhombus and CDEF is a parallelogram. ∠FGJ = 80° and ∠EFG = 94°.
- Find ∠BFC
- Find ∠FED
(a)
∠JKF = ∠JGF = 80°
∠KFJ
= (180° - 80°) ÷ 2
= 100° ÷ 2
= 50° (Isosceles triangle)
∠BFC
= 90° - 50°
= 40°
(b)
∠CFE
= 360° - 94° - 90° - 50°
= 126° (Angles at a point)
∠DEF
= 180° - 126°
= 54° (Interior Angles, CF//DF)
Answer(s): (a) 40°; (b) 54°