I have a input output table and I can't figure out the rule here is the chart

X. Y
_______________
1. | 3
4. | 7
7. | 11

Can u figure it out I'm having a really hard time with this problem!!!!

slope between (1,3) and (4,7) = 4/3

slope between (4,7) and (7,11) = 4/3

so it looks like the relation is linear

let the equation by y = (4/3)x + b
Plug in (1,3)
3 = (4/3) + b
b = 3-4/3 = 5/3

equation:
y = (4/3)x + 5/3

or

3y = 4x + 5 ----> 4x - 3y + 5 = 0