Answer:
(d) a = 30°
b = 120°
(e) a = 115°
Explanation:
(d)
∠EAC + ∠EDC = 180°
(55+a)° + 95° = 180°
a = (180-95-55)°
= 30°
ΔOAC = isosceles triangle
∠OAC = ∠OCA = 30°
∠AOC (minor) = 180° - 30° - 30°
= 120°
∠AOC (major) = 360° - 120°
= 240°
∠AOC (major) = 2 × ∠ABC
240° = 2 × b
b = 120°
(e)
2 × ∠ACD = 230°
∠ACD = 115°
∠ABD = ∠ACD
a = 115°