Question

If two sides of a cyclic quadrilateral are parallel, prove that :
1. Its are the two that are equal
2. its diagonals are equal.

Answer 1

1. in a cyclic quadrilateral, the opposite angles are equal and parallel so you can say the opposite angles are equal by property of cyclic quadrilateral
2.By angle bisector property of a cyclic quadrilateral the opposite angle bisected by the diagonal are equal.