y=mx+b solve for m

To solve for m we want to get m by itself on one side of the equals sign, with everything else on the other side. First we subtract b from both sides, to get it out of the right side of the equation:

y - b = mx + b - b

y - b = mx

Now we divide both sides by x, to get m completely by itself:

(y-b)/x = (mx)/x

(y-b)/x = m

So m is equal to (y-b)/x.