Question

Find the area of a triangle if its sides are $9cm,12cmand15cm$

Answer 1

We know in triangle if the three sides are $a,b,c$ then the area of the triangle is

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

Where $s=\frac{(a+b+c)}{2}$

Given $a=9,b=12,c=15$

Therefore $s=\frac{(9+12+15)}{2}=18$

Therefore area $=\sqrt{18\times 9\times 6\times 3}=54$

So the area of the triangle is $54c{m}^2$