Answer/Step-by-step explanation:
Rob is incorrect because the graph line don't go trough the origin.
If the graph of a relationship is a line or a ray through the origin, then it is proportional. If it is a line or ray that does not pass through the origin, then it is not proportional. Also, if it is not linear, then it is not proportional.
Proportional relationships in mathematics occur when two variables always change by the same multiple. Proportional relationships use the model y = kx, where k is a constant multiplier that shows the relationship between x and y. The graph is a straight line that always passes through (0,0).
