Thread: Help Solving

Started studying Algebra recently and need help in solving the following:

Make c the subject of the equation:

$\displaystyle ab - ac = bc$

So far i've got:

$\displaystyle ac + bc = ab$

Then i try isolate c on the left:

$\displaystyle \frac {a+b}{c} = ? $

Is that in the right direction? Any tips would be greatly appreciated!

Originally Posted by BIOS

Started studying Algebra recently and need help in solving the following:

Make c the subject of the equation:

$\displaystyle ab - ac = bc$

So far i've got:

$\displaystyle ac + bc = ab$

[snip]

=> c(a + b) = ab

=> c = ....

$\displaystyle c = \frac {ab}{a+b}$

I don't know how i missed that! Argh. Thanks so much for the reply. Exactly the same type of equation i had problems with yesterday. Extracting the subject when it was multiplied by another variable. Thanks again!