Question

$y=\frac{qx}{p}$
write $x$ in terms of $p,q$ and $y$

Answer 1

$y=\frac{qx}{p}$

$\Rightarrow y\times p=\frac{qx\times p}{p}$

$\Rightarrow py=qx$

$\Rightarrow \frac{p\times y}{q}=\frac{qx}{q}$

$\Rightarrow \frac{py}{q}=x$

$\therefore x=\frac{py}{q}$