Question

How do u find the height of the base??

Answer 1

`\bf \textit{height of an equilateral triangle}\\\\ h=\cfrac{s√(3)}{2}\qquad \begin{cases} s=length~of\\ \qquad a~side\\ ------\\ s=12 \end{cases}\implies h=\cfrac{12√(3)}{2}\implies h=6√(3)\\\\ -------------------------------\\\\ \textit{area of an equilateral triangle}\\\\ A=\cfrac{s^2√(3)}{4}\qquad \begin{cases} s=length~of\\ \qquad a~side\\ ------\\ s=12 \end{cases}\implies A=\cfrac{12^2√(3)}{4}\implies A=36√(3)`

and of course as you already know the volume of the prism is just the area of the base times the length, namely A * 20.