Carly used 15 centimeters of tape to wrap 3 presents. How many presents did Carly wrap if she used 45 centimeters of tape? Assume the relationship is directly proportional.

In order for the function to be linear, what must m be and why? m = 22 because the rate of change is 1. m = 20 because the rate of change is 3. m = 22 because the rate of change is -1. m = 20 because the rate of change is -3.