the measures of a pair of two adjacent sides of a parallelogram are 15cm and 20 cm.if the length of one of its diagonal is 25cm, find the area of the parallelogram

Answer 1

The parallelogram has sides 15cm 20cm 15cm 20cm

The diagonal of length 25cm divide it into two congruent triangles

Using the heron formula to find the area of a triangle and multiplying by two we get the area of parallelgram

Triangle with sides 15cm 20 cm 25 cm

Putting the values in heron formula we get

sqrt(s(s-a)(s-b)(s-c))
= sqrt(30 * 15*10*5)
= 15*2*5
= 150

Area of parallelogram =150 *2
= 300

Answer 2

The figure is a rectangle, since

15^2 + 20^2 = 25^2

The area is thus 15*20 = 300