Question

Find area of a triangle whose sides measures 13 cm,14cm,15cm.

Answer 1

Let $a=13$, $b=14$, $c=15$ then $s=\frac{1}{2}(a+b+c)=21$

$(s-a)=8(s-b)=7(s-c)=6$

Area $=\sqrt{s(s-a)(s-b)(s-c)}$

$=\sqrt{21\times 8\times 7\times 6}$

$=84{cm}^2$