Diagonals in the quadrilateral ABCD the line segments AC and BD are called its diagonals.

If the diagonals AC,BD of a quadrilateral ABCD, intersect at O, and separate the quadrilateral into four triangles of equal area, show that quadrilateral ABCD is a parallelogram.

In a quadrilateral ABCD, with unequal sides if the diagonals AC and BD intersect at right angles, then

If ABCD is a quadrilateral whose diagonals AC and BD intersect at O, then

In Figure,ABCD is a cyclic quadrilateral in which AC and BD are its diagonals.If /_DBC=55^(@) and /_BAC=45^(@), find /_BCD

In the given figure ABCD is a cyclic quadrilateral in which AC and BD are its diagonals. If angle DBC = 55 ^(@) and angle BAC = 45 ^(@), find angle BCD.

In Fig 10.33, ABCD is a cyclic quadrilateral in which AC and BD are its diagonals.If /_DBC=55^(@)/_BAC=45^(@) find ? BCD

In a parallelogram ABCD, E and F are the mid-points of sides AB and CD respectively. Show that the line segments AF and EC trisect the diagonal BD.

Diagonals AC and BD of a quadrilateral ABCD intersect at O in such a way that ar (AOD)=ar(BOC). Prove that ABCD is a trapezium.