A proportional relationship is characterized by a straight line passing through the origin (0,0) and having a constant ratio between the variables.
Based on your description:
- Graph A shows a straight line with a negative slope having x and y intercepts. This does not pass through the origin.
- Graph B shows a straight line with a positive slope having a y intercept above the origin. This also does not pass through the origin.
- Graph C shows an increasing concave up curve initiating at the origin. This suggests a nonlinear relationship, not proportional.
- Graph D shows a straight line with a unit slope. If it passes through the origin, it indicates a proportional relationship.
Thus, the graph that shows a proportional relationship is:
D.