1. ## Tranpose

Make x the subject of

y= (r+x)/(1-rx)

2. $y= \frac{r+x}{1-rx}$

$y(1-rx)=(r+x)$

$y-yrx = r+ x$

$y-r = x+ yrx$

$y-r = x(1+ yr)$

$x= \frac{y-r}{1+yr}$

3. thanks anon.1 getting back into maths after 10 years and some things appear harder than they actually are.

4. Haha no problem. Good luck!