If x is directly proportional to the square root of y, then y is inversely proportional to...?
Thank you in advance!
right. so you know $\displaystyle \displaystyle x = k \sqrt y$ and you want to get to $\displaystyle \displaystyle y = \frac C{f(x)}$ (by solving for y and, perhaps, rearranging)
where $\displaystyle \displaystyle C$ is a constant and $\displaystyle \displaystyle f(x)$ is some function of $\displaystyle \displaystyle x$. That $\displaystyle \displaystyle f(x)$ is the answer to your question. can you find it?