Suppose $\displaystyle {z}$ varies directly with $\displaystyle {x}$ and inversely with the square of $\displaystyle {y}$. If $\displaystyle {z}={16}$ when $\displaystyle {x}={4}$ and $\displaystyle {y}={2}$, what is $\displaystyle {z}$ when $\displaystyle {x}={9}$ and $\displaystyle {y}={8}$?
$\displaystyle {z}=$ Preview Question 6