Given that BCDE is a trapezium and BCE is an isosceles triangle, find the values of
- ∠r
- ∠s
(a)
∠r
= 180° - 86°
= 94° (Interior angles)
(b)
∠ECB
= 86° ÷ 2
= 43° (Exterior angle of a triangle)
∠DEC = ∠ECB = 43° (Alternate angles)
∠s
= 180° - 89° - 43°
= 48° (Angles sum of triangle)
Answer(s): (a) 94°; (b) 48°