In the figure, WXYZ is a parallelogram. YB, BC and WX are straight lines. WZA is an isosceles triangle.
- Find ∠i.
- Find ∠j.
(a)
∠YBW = ∠XWC = 58° (Corresponding angles, WX//BY)
∠BAW
= 180° - ∠YBW - ∠BWA
= 180° - 58° - 20°
= 102° (Angles sum of triangle)
∠ZAW
= 180° - 102°
= 78° (Angles on a straight line)
∠AZW = ∠ZAW = 78° (Isosceles triangle)
∠i
= ∠AZW
= 78° (Corresponding angles, XY//WZ)
(b)
∠j
= 180° - 78° - 78°
= 24° (Isosceles triangle WZA)
Answer(s): (a) 78°; (b) 24°