Question

the adjacent sides of a parallelogram are 21cm and 28cm. if its one diagonal is 35 cm.find the area of the parallelogram .

Answer 1

Hii mate!!

a=21cm
b=28cm
c=35cm

s=a+b+c/2
=42

BY HERON'S FORMULA

AREA OF IIGM (FIRST PART)
$\sqrt{42 (42 - 21)(42 - 28)(42 - 35)}$
$\sqrt{42 \times 21 \times 14 \times 7}$
$\sqrt{7 \times 6 \times 7 \times 3 \times 7 \times 5 \times 7}$

$7 \times 7 \sqrt{6 \times 3 \times 5}$
$49 \sqrt{3 \times 2 \times 3 \times 5}$
$49 \times 3 \sqrt{5 \times 2}$
$147 \sqrt{10}$

AREA OF IIGM (SECOND PART)

=147√10×2
=294√2ANS..

Thanks
I THINK IT HELPS..
@garu1678