Answer :
For a proportional relationship, there must be a constant ratio between x and y. This means the relationship between the two variables should be of the form
[tex]y=kx[/tex]where k is any constant.
Now, in our case of y = 3/4 x, we see that y and x are related by a constant 3/4 which means there is a constant ratio between the two variables; therefore, the relationship is proportional.