[tex]\bf \textit{area of a triangle}=A=\cfrac{1}{2}bh\qquad
\begin{cases}
b=base\\
h=\textit{height or altitude}
\end{cases}\\\\
-----------------------------\\\\
\textit{area of a trapezoid}\\\\
A=\cfrac{h}{2}(a+b)\qquad
\begin{cases}
a=\textit{base, or one of the parallel sides}\\
b=\textit{base, or the other parallel side}\\
h=\textit{height, the distance between both}\\
\qquad \textit{parallel sides}
\end{cases}[/tex]
