The figure is not drawn to scale. AB//DC and CB//EA. Triangles AEB and BCD are isosceles triangles. Find
- ∠i
- ∠j.
(a)
∠BCD = ∠BAE = 78° (CB//EA, BA//CD)
∠ABE
= (180° - 78°) ÷ 2
= 102° ÷ 2
= 51° (Isosceles triangle)
∠CBD
= 180° - 78° - 78°
= 24° (Isosceles triangle)
∠i
= 180° - 78° - 51° - 24°
= 27° (Interior angles, BA//CD)
(b)
∠j
= 180° - 29° - 27°
= 124° (Angles sum of triangle)
Answer(s): (a) 27°; (b) 124°