3x + 1 = y
x: 1 | 2 | 3 |
------|---|--- |----------------
y: 4 | 7 | 10|
so make points at (1,4) (2,7) and (3,10), and connect them to get the line
4x + 1
x: 1 | 2 | 3
----------------
y: 5 | 9 | 13
Make points at (1,5) (2,9) and (3,13)
IF they do not intersect yet, continue making points until they intersect. Make note of the point in which they intersect, and that is your answer
hope this helps