From what it seems, thus chart is proportional. This is because the unit of proportionality, which would be X: 1 and Y: 3, is constant. The way we find this is dividing the X by itself to get to one. And whatever we do to one side, we have to do the other side. Hence the unit of proportionality is X: 1 and Y: 3.
Knowing this, we’re able to use the equation -
y = 3x
Hopefully this made sense! If you have any questions, please ask. Have a great day!