Prove that if the external angle obtained by producing the side of a quadrilateral is equal to the internally oppoiste angle, then the quadrilatera wil be cyclic.

Prove that if two opposite angles and two opposite sides of any quadrilateral be parallel , then it is a parallelogram.

Answer any one question : Prove that the quadrilateral foemed by the internal bisectors of the four angles of a quadrilateral is cyclic.

Prove that the area of the parallelogram produced by joining the mid-points of the sides of a quadrilateral taken in order is half the area of the quadrilateral.

The opposite angles of a cyclic quadrilateral are ……………

Of the quadrilateral if the opposite angles are equal the sum of angle B and angle C will be

If an exterior angle of a cyclic quadrilateral be 50^@ , then the interior opposite angle is___

Prove that the internal bisector of any angle of a cyclic quadrilateral and the external bisector of its opposite angle intersect each other on the circumference of the circle.

Prove that the opposite angles of a cyclic quadrilateral are suplemenary.

Prove that two angles attached to the parallel sides of any isosceles trapezium are equal to each other .