Find the area of a quadrilateral one of whose diagonals is 40 cm and the lengths of the perpendiculars drawn from the opposite vertices on the diagonal are 16 cm and 12 cm.



Given : A quadrilateral


Diagonal AC = 40 cm


Perpendiculars to diagonal AC are: BL = 16 cm and DM = 12 cm


Now,


Area (quad. ABCD) = area (ABC) + area (ADC)


Area of triangle = × (base) × (height).


Therefore


Area of quad ABCD = × (AC) × (BL) + × (AC) × (DM)


= × (40) × (16) + × (40) × (12) = 320 + 240 = 560 cm2


Therefore area of the quadrilateral ABCD is 560 cm2.


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