[tex]\textit{area of a sector of a circle}\\\\ A=\cfrac{\theta \pi r^2}{360} ~~ \begin{cases} r=radius\\ \theta =\stackrel{degrees}{angle}\\[-0.5em] \hrulefill\\ r=9\\ \theta =120 \end{cases}\implies \begin{array}{llll} A=\cfrac{(120)\pi (9)^2}{360}\implies A=27\pi \\\\\\ \stackrel{using~\pi =3.14}{A\approx 84.8} \end{array}[/tex]
