Question

Find the area of a triangle. whose sides are $8cm,10cm$ and $15cm$.

Answer 1

Given sides of triangle are

$a=8cmb=10cmc=15cm$

$s=\frac{a+b+c}{2}=\frac{8+10+15}{2}=\frac{33}{2}$

$(s-a)=\frac{33}{2}-8=\frac{33-16}{2}=\frac{17}{2}$

$(s-b)=\frac{33}{2}-10=\frac{33-20}{2}=\frac{13}{2}$

$(s-c)=\frac{33}{2}-15=\frac{33-30}{2}=\frac{3}{2}$

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

$=\sqrt{\frac{33}{2}\times \frac{17}{2}\times \frac{13}{2}\times \frac{3}{2}}$

$=\sqrt{\frac{21879}{16}}=\frac{147.9}{4}=36.97c{m}^2$