Answer:
[tex]\large\boxed{q=4P+4r}[/tex]
Step-by-step explanation:
[tex]\dfrac{q}{4}-r=P\qquad\text{muliply both sides by 4}\\\\4\!\!\!\!\diagup^1\cdot\dfrac{q}{4\!\!\!\!\diagup_1}-4r=4P\\\\q-4r=4P\qquad\text{add}\ 4r\ \text{to both sides}\\\\q=4P+4r[/tex]