# make y the subject...

• November 1st 2008, 02:16 PM
Ant
make y the subject...
$3y/(y-1) = x$

I can't seem to make y the subject of the above formula....I must be having some kind of mental lapse here!
• November 1st 2008, 02:20 PM
mr fantastic
Quote:

Originally Posted by Ant
$3y/(y-1) = x$

I can't seem to make y the subject of the above formula....I must be having some kind of mental lapse here!

$\frac{3y}{y - 1} = x$

$\Rightarrow 3y = x(y - 1) = xy - x$

$\Rightarrow 3y - xy = -x$

$\Rightarrow y (3 - x) = -x$

$\Rightarrow y = \frac{-x}{3 - x} = \frac{x}{x - 3}$.
• November 1st 2008, 02:23 PM
Ant
thankyou!