True.
A proportional relationship means that the ratio of the two values remains constant.
Calculating the ratios for the given points:
- For (3, 9): \( \frac{9}{3} = 3 \)
- For (4, 12): \( \frac{12}{4} = 3 \)
- For (5, 15): \( \frac{15}{5} = 3 \)
Since the ratios are all equal (3), the table represents a proportional relationship.