# Math Help - I need help

1. ## I need help

This is super easy to some of you but I can't seem to figure this out.

r = m/l + n/k

solve for m

2. ## Re: I need help

Originally Posted by ihatemath123
This is super easy to some of you but I can't seem to figure this out.

r = m/l + n/k

solve for m
\displaystyle \begin{align*} r &= \frac{m}{l} + \frac{n}{k} \\ r - \frac{n}{k} &= \frac{m}{l} \\ \frac{k\,r - n}{k} &= \frac{m}{l} \\ \frac{l\left(k\,r - n\right)}{k} &= m \\ m &= \frac{k\,l\,r - l\,n}{k} \end{align*}

3. ## Re: I need help

r = m/l + n/k

You want to isolate m. So, first you move n/k to the other side. r - n/k = m/l. Multiply both sides by l. rl - (nl/k) = m.