Answer:
The equation y = -3r + 13 does not belong with the other three.
Step-by-step explanation:
We have 4 equations
The first 3 equations have relations between two variables x and y
So they are linear equations of two variables x and y
The fourth equation has a relation between two variables r and y
So it is a linear equation of two variables r and y
The fourth equation does not belong to with the first three equations because it has a different variable r
The equation y = -3r + 13 does not belong with the other three.