From the graph, we can that the relationship is proportional and the constant of proportionality is 3
What is constant of proportionality
The constant of proportionality is a numerical value that relates two variables in a proportional relationship.
In a proportional relationship, when one variable changes, the other changes in such a way that the ratio between them remains constant.
This is represented by the equation
y = kx
y is the dependent variable.
x is the independent variable.
k is the constant of proportionality.
From the graph, at x = 1 y = 3, hence
3 = k * 1
k = 3