Answer
$y=\displaystyle \frac{40}{x}$
Work Step by Step
If $y$ varies inversely as $x,$ then $y=\displaystyle \frac{k}{x}.$
Given $y=5, x=8$, we find k
$ 5=\displaystyle \frac{k}{8}\qquad$... multiply with 8
$k=40$
$y=\displaystyle \frac{40}{x}$
