Given the equation below,
[tex]\frac{B(q-L)}{h}=r[/tex]Solving for q, by making q the subject of formula from the above equation
Multiply both sides by h
[tex]\begin{gathered} h\times\frac{B(q-L)}{h}=r\times h \\ B(q-L)=rh \end{gathered}[/tex]Divide both sides by B
[tex]\begin{gathered} \frac{B(q-L)}{B}=\frac{rh}{B} \\ (q-L)=\frac{rh}{B} \end{gathered}[/tex]Add L to both sides
[tex]\begin{gathered} q-L+L=\frac{rh}{B}+L \\ q=\frac{rh}{B}+L \end{gathered}[/tex]Hence, the answer is
[tex]q=\frac{rh}{B}+L[/tex]