Question

the length of two adjacent sides of a parallelogram are 40 cm 50 cm one of its diagonal is 20 centimetre find area of parallelogram

Answer 1

It will be twice the area of triangle created by 40,50,20 triangle.
to find the area use herons formula

$\sqrt{s(s - a)(s - b)(s - c)}$
S=(a+b+c)/2

Answer : s=(40+50+20)/2 = 55
Ar of triangle = sqrt(55x15x5x35)=25sqrt(231)
Ar of parallelogram = 50sqrt (231)