Y= mx + b (b) your b = y - mx b = x- ym b = y + mx b = mx-y

The answer is b=y-mx.

You would subtract b from both sides, giving you y-b=mx. You have to get b isolated, so you'd subtract y from both sides, giving you -b=mx-y. The b is positive, so you'd multiply -1 to both sides, giving you b=-mx+y. By rearranging the letters you get b=y-mx.