In the figure, VWXY is a parallelogram. XA, AB and VW are straight lines. VYZ is an isosceles triangle.
- Find ∠b.
- Find ∠c.
(a)
∠XAV = ∠WVB = 61° (Corresponding angles, VW//AX)
∠AZV
= 180° - ∠XAV - ∠AVZ
= 180° - 61° - 20°
= 99° (Angles sum of triangle)
∠YZV
= 180° - 99°
= 81° (Angles on a straight line)
∠ZYV = ∠YZV = 81° (Isosceles triangle)
∠b
= ∠ZYV
= 81° (Corresponding angles, WX//VY)
(b)
∠c
= 180° - 81° - 81°
= 18° (Isosceles triangle VYZ)
Answer(s): (a) 81°; (b) 18°
