Hey there! I'm happy to help!
A proportional relationship is a straight line that passes through the origin, which is (0,0). If you look at Graph 3, it looks like the line is straight, but it does not look like it will pass through (0,0). Therefore, Graph 3 does not show a proportional relationship.
Graph 4, however, does look like straight line and it does look like it will pass through (0,0). Therefore, Graph 4 does show a proportional relationship.
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