In the figure, CDEF is a parallelogram. EH, HJ and CD are straight lines. CFG is an isosceles triangle.
- Find ∠x.
- Find ∠y.
(a)
∠EHC = ∠DCJ = 61° (Corresponding angles, CD//HE)
∠HGC
= 180° - ∠EHC - ∠HCG
= 180° - 61° - 19°
= 100° (Angles sum of triangle)
∠FGC
= 180° - 100°
= 80° (Angles on a straight line)
∠GFC = ∠FGC = 80° (Isosceles triangle)
∠x
= ∠GFC
= 80° (Corresponding angles, DE//CF)
(b)
∠y
= 180° - 80° - 80°
= 20° (Isosceles triangle CFG)
Answer(s): (a) 80°; (b) 20°