Answer
$h=\displaystyle \frac{d^{2}}{k^{2}}$
Work Step by Step
We solve this equation for $h$:
$d=k\sqrt{h}$
First divide by $k$:
$\frac{d}{k}=\sqrt{h}$
Then square both sides:
$\frac{d^{2}}{k^{2}}=h$
Thus:
$h=\displaystyle \frac{d^{2}}{k^{2}}$