Well, I am not very sure. But, the things I remembered when I was reading my book, was that, you should assign values for your x and y.
Assign some values for x and y that will satisfy the equation. Example:
If x is 1, then y will be 8, so x=1 and y=8
If x is 2, then y will be 11, so x=2 and y=11
So now you have some values:
y=8, 11 (remember to align the numbers, 1 is paired with 2 so align them!)
Now that you have values now, graph it in the cartesian or coordinate plane, I am not sure about the exact name, or i think they are just the same. The graph of linear equations are always a straight line.