[tex]\bf \textit{volume of a rectangular prism}\\\\
V=Bh~~
\begin{cases}
B=area~of\\
\qquad its~base\\
h=height\\
-----------\\
V=16y^4+16y^3+48y^2
\end{cases}
\\\\\\
16y^4+16y^3+48y^2=Bh\implies 16y^2(y^2+y+3)=Bh[/tex]
so since its just two factors, you can pick either for the "B" or "h", or one can say that the trinomial is the "B", because it can be factored into a couple more binomials, either way will work.
