one interior angle in a regular polygon is 162° how many sides does the polygon have?

[tex]\bf \textit{sum of all interior angles in a regular polygon}\\\\ S=180(n-2)\implies n\theta =180(n-2)\quad \begin{cases} n=\textit{number of sides}\\ \theta =\textit{interior angle}\\ ----------\\ \theta =162 \end{cases} \\\\\\ n(162) =180(n-2)\implies 162n=180n-360 \\\\\\ 360=18n\implies \cfrac{360}{18}=n\implies 20=n[/tex]