Angle bisectors in a parallelogram
The applet illustrates thatifin the parallelogram ABCD (AB > AD), the angles' bisectors AE, BF, CG and DH
are drawn, which intersect at points K, I, N and G, then the quadrilateral KING
is a rectangle, the diagonals of the rectangle KING are parallel to the sides
of the parallelogram, and thelength of the diagonal of the rectangle is the difference between the lengths
of the sides of the parallelogram.