[tex] \bf \textit{area of a trapezoid}\\\\
A=\cfrac{h(a+b)}{2}~~
\begin{cases}
a,b=\stackrel{bases}{parallel~sides}\\
h=height\\[-0.5em]
\hrulefill\\
a=15.8\\
b=21.8\\
h=11.7
\end{cases}\implies A=\cfrac{11.7(15.8+21.8)}{2}
\\\\\\
A=\cfrac{11.7(37.6)}{2}\implies A=219.96 [/tex]
