In the adjoining figure, show that ABCD is a parallelogram.
Calculate the area of ‖gm ABCD.
In the given figure consider ABD and BCD
Area of ABD = x base x height = x AB x BD
= x 5 x 7 = -------- 1
Area of BCD = x base x height = x DC x DB
= x 5 x 7 = ----------2
From 1 and 2 we can tell that area of two triangle that is ABD and BCD are equal
Since the diagonal BD divides ABCD into two triangles of equal area and opp sides AB = DC
ABCD is a parallelogram
Area of parallelogram ABCD = Area of ABD + Area of BCD
= = cm2 = 35 cm2
Area of parallelogram ABCD = 35cm2