The given formula is
[tex]W=X+\text{Xyz}[/tex]First, subtract X from each side.
[tex]\begin{gathered} W-X=X-X+\text{Xyz} \\ W-X=\text{Xyz} \end{gathered}[/tex]Second, divide both sides by Xy.
[tex]\begin{gathered} \frac{W-X}{Xy}=\frac{\text{Xyz}}{Xy} \\ \frac{W-X}{Xy}=z \end{gathered}[/tex]At last, arrange the z on the left. Therefore, the final expression is
[tex]z=\frac{W-X}{Xy}[/tex]