Question

A parallelogram has two sides 60 m and 25 m and a diagonal 65 m long.

What is the area of a parallelogram ?

• A. 1500$m^2$
• B. 1800$m^2$
• C. 1300$m^2$
• D. 1200$m^2$

Answer 1

The correct option is A 1500$m^2$

Let $s$ be the perimeter of triangle $ABC.$ So,

$s=\frac{(25+65+60)}{2}=75$

Now , Area o f triangle ABC

$=\sqrt{75\times (75­-25)\times (75­-65)\times (75-60)}$

$=750$

Area of parallelogram $ABCD$= $2\times Areaof\Delta ABC$

= $2\times 750$

= $1500$ $m^2$