To get it in slope-intercept form, which is y = mx + b, you're just trying to isolate the y on one side, like you would solve for anything else. Don't let the fact that there's a second variable in there throw you off.
If you want to isolate the y on the left side, you need to get rid of the -2x. If that were -10, you would add 10 to both sides. This is the same thing: you add 2x to both sides.
That will isolate your y. Then just rearrange the right side to get it in proper mx + b order. Just watch the signs!
I don't know if they want you to use any particular method for graphing, but you can use the x and y intercepts.
y intercept is where x is 0, hence (0, y)
x intercept is where y is 0, hence (x, 0)
You can always plug in one variable and solve for the other to get your graphing point. That will always work. That's what you'll need to do to get the x intercept. The y intercept is the b in the slope-intercept form, so you'll already have that number.