Question

If the perimeter and radius of a sector are 38 cm and 9 cm respectively, find its area.

Answer 1

Given, $r=9cm$, perimeter $=38cm$
Perimeter $=l+2r=38$
i.e., $l+18=38$
$l=38-18=20cm$
$\therefore$ Area $=\frac{lr}{2}$

$=\frac{20\times 9}{2}$

$=90c{m}^2$