1) you start knowing that the slope-intercept equation is y=mx+b. M stands for your slope so you just plug 2 in for m. Then you plug in the x to see how to make it equal 1. As you look at it you realize that 2*-3 is -6 and you need to add 7 to get to one. Therefore the seven would be the B.
2) Since there is no slope the lines just go on the horizon at the y point of 4 or 3.
