Answer:
The function r(x) represents a constant rate per unit change in x.
Step-by-step explanation:
This is because when you increase in 2, it goes from 37 to 25, a decrease in 12, then when the x goes from 2 to 3, then it has to drop down by 6, or else it won't be linear. It does. 25-6 is 19. Then it goes from 3 to 5, meaning it has an increase of 2 in x, meaning it has to drop down in 12 to be linear, It does. 19-12 is 7. So it is linear, meaning it has a constant rate per unit change in x.