Diagonals AC and BD of a quadrilateral ABCD intersect each other at P. Show thatar (APB) × ar (CPD) = ar (APD) × ar (BPC).

[Hint: From A and C, draw perpendiculars to BD]


Let us construct AM perpendicular to BD

Now,


Area (APB)*Area (CPD)


=


=


Area (APD)*Area (BPC)


=


=


Hence,


Area (APB)*Area (CPD) = Area (APD)*Area (CPB)


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