In the figure, CDEF is a parallelogram. EH, HJ and CD are straight lines. CFG is an isosceles triangle.
- Find ∠a.
- Find ∠b.
(a)
∠EHC = ∠DCJ = 64° (Corresponding angles, CD//HE)
∠HGC
= 180° - ∠EHC - ∠HCG
= 180° - 64° - 20°
= 96° (Angles sum of triangle)
∠FGC
= 180° - 96°
= 84° (Angles on a straight line)
∠GFC = ∠FGC = 84° (Isosceles triangle)
∠a
= ∠GFC
= 84° (Corresponding angles, DE//CF)
(b)
∠b
= 180° - 84° - 84°
= 12° (Isosceles triangle CFG)
Answer(s): (a) 84°; (b) 12°
