Question

diagonals of cyclic quadrilateral ABCD are congruent show that AD=BC and AB parallel CD​

Answer 1

ABCD is a quadrilateral in which both the diagonals are congruent,where both the diagonal AC and BD intersect each other at O. Since, Both the diagonals are equal in length. Hence, ΔOAB, ΔOBC,ΔOCD,ΔODA are isosceles triangles. Also,it is concluded that the all sides of quadrilateral are equal.Therefore AD equal to BC and AB parallel to CD(by c.p.c.t)