Answer: [tex]z = \frac{pu-W}{p}\\\\[/tex]
We can write this as z = (pu-W)/p
This is the single fraction with pu-W up top and p in the denominator.
Other answers are possible.
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Work Shown:
[tex]W=p(u-z)\\\\W=pu-pz\\\\W+pz=pu\\\\pz=pu-W\\\\z=\frac{pu-W}{p}\\\\[/tex]
An alternative method could have these steps instead
[tex]W=p(u-z)\\\\u-z = \frac{W}{p}\\\\-z = \frac{W}{p}-u\\\\z = -\frac{W}{p}+u\\\\z = -\frac{W}{p}+\frac{pu}{p}\\\\z = \frac{-W+pu}{p}\\\\z = \frac{pu-W}{p}\\\\[/tex]
