In Fig. 10.138, if AE||DC and AB=AC, the value of ∠ABD is
∠EAP = ∠BCA (Corresponding angles)
∠BCA = 70°
∠CBA = ∠BCA (Angles opposite to equal sides are equal)
∠CBA = 70°
Now,
∠ABD + ∠CBA = 180°
∠ABD + 70 = 180°
∠ABD = 110°