Question

Find the area of a triangle in ${mm}^2$, whose sides are: $18mm,24mm$ and $30mm$.

Answer 1

Area of triangle with sides a, b, and c and s $=\frac{a+b+c}{2}$ is $\sqrt{s(s-a)(s-b)(s-c)}$.
For triangle with sides 18 mm, 24 mm and 30 mm, $s=\frac{18+24+30}{2}=36mm$
Area of the triangle with sides 18 mm, 24 mm and 30 \ mm

$=\sqrt{36(36-18)(36-24)(36-30)}$

$=\sqrt{36\times 18\times 12\times 6}$

$=\sqrt{18\times 2\times 18\times 6\times 2\times 6}$

$=18\times 6\times 2$

$=216{mm}^2$