#### Answer

$k=30$, $y=\frac{30}{x}$

#### Work Step by Step

If y varies inversely as x, we know that the variables x and y can be related by the function $y=\frac{k}{x}$, where k is the constant of proportionality.
If $y=6$ when $x=5$, then we know that $6=\frac{k}{5}$. Multiply both sides by 5.
$k=6\times5=30$
Therefore, the constant of variation is $k=30$ and the inverse variation equation is $y=\frac{30}{x}$.