# rearranging formulae with fractions

• Oct 14th 2009, 12:02 PM
maths noob
rearranging formulae with fractions
how would i do this

y=mx+x/2m
• Oct 14th 2009, 12:07 PM
e^(i*pi)
Quote:

Originally Posted by maths noob
how would i do this

y=mx+x/2m

Do you want to solve for x, y or m ?

$y = mx + \frac{x}{2m}$
• Oct 14th 2009, 12:31 PM
maths noob
ooops x
• Oct 14th 2009, 12:33 PM
e^(i*pi)
Quote:

Originally Posted by maths noob
ooops x

Because x is in both terms it can be factored out:

$
y = mx + \frac{x}{2m} = x\left(m+\frac{1}{2m}\right)
$

Divide through to isolate x:

$x = \frac{y}{\left(m+\frac{1}{2m}\right)}$

That can be tidied up by multiplying through by $2m$

$x = \frac{2my}{2m^2+1}$