SAT Question 08b7a3f5: Area and Volume answer and explanation with Desmos solution

It's given that a triangular prism has a volume of $216$ cubic centimeters (${\text{cm}}^3$) and the volume of a triangular prism is equal to $Bh$, where $B$ is the area of the base and $h$ is the height of the prism. Therefore, $216=Bh$. It's also given that the triangular prism has a height of $8$ cm. Therefore, $h=8$. Substituting $8$ for $h$ in the equation $216=Bh$ yields $216=B\left(8\right)$. Dividing both sides of this equation by $8$ yields $27=B$. Therefore, the area, ${\text{in cm}}^2$, of the base of the prism is $27$.