Question

ABCD is a parallelogram the circle so A B and C intersect CD at e prove that a equal to a d

Answer 1

Given ABCD is a parallelogram passing through A, B, C and intersecting CD at E.∠B = ∠D [Opposite angles of a parallelogram are equal]  → (1) Since ABCE is a cyclic quadrilateral. Recall that “exterior angle of a cyclic quadrilateral is equal to interior opposite angle”. Hence ∠B = ∠AED → (2) From (1) and (2), we get∠D = ∠AED    Therefore AE = AD [Since in a triangle, sides opposite to equal angles are equal]