Answer
$x=\displaystyle \frac{kyz}{\sqrt{w}}$
$y=\displaystyle \frac{x\sqrt{w}}{kz}$
Work Step by Step
$x$ varies directly as $y:\qquad x=ky$
$x$ varies directly as $z:\qquad x=kz$
$x$ varies inversely as $\sqrt{w} :\displaystyle \qquad x=\frac{k}{\sqrt{w}}$
Combined (jointly): $\displaystyle \qquad x=\frac{kyz}{\sqrt{w}}$
Solving for $y,$
(multiply both sides with $\displaystyle \frac{\sqrt{w}}{kz})$
$\displaystyle \frac{x\sqrt{w}}{kz}=y$
