Prove that the bisectors of the interior angles of a rectangle form a rectangle.
∠1=902=45o
Similarly, ∠2=902=45o
In △AXD,
=180−45−45=90o
∠WXY=90o [vertically opposite angles]
Similarly in △BCZ,
∠CZB=∠WZY=90o
Since all the angles will be 90o and hence it will be a rectangle.