## Intermediate Algebra for College Students (7th Edition)

$q=\displaystyle \frac{pf}{p-f}$
Get rid of fractions (multiply with LCD=pqf) $qf+pf=pq\qquad$ ... add $-qf$ $pf=pq-qf\qquad$ ... factor out q $pf=q(p-f)\qquad$ ... divide with $(p-f)$ to isolate $q$ $\displaystyle \frac{pf}{p-f}=q$ $q=\displaystyle \frac{pf}{p-f}$