And so what you do is, you take each of the equation and you like, when you graph it, you like to put it in kind of the y-intercept form or slope intercept form and so you do that, so you say, well let me solve both of these for b so if you want to solve this first equation for b you just subtract 2a from both sides if you subtract 2a from both sides of this first equation you get b is = to -2a + 3.