Marcus is eating a meal that is made up of an entr_e that is 45 calories per ounce and a side dish that is 30 calories per ounce. He wants his meal to total 510 calories. Let e represent the number of ounces of the entr_e that he eats, and let s represent the number of ounces of the side dish that he eats. Which function relates the number of ounces of the side dish that he eats to the number of ounces of the entr_e that he eats?

The answer is s = - 3/2e + 17.

e - the number of ounces of the entree

s - the number of ounces of the side dish

Entree has 45 calories per ounce: E = 45e

Side dish has 30 calories per ounce: S = 30s

Meal is total 510 calories: x = 510

Meal consists of the entree and the side dish:

x = E + S

Now, just substitute:

510 = 45e + 30s

Now, to find the function that relates the number of ounces of the side dish that he eats to the number of ounces of the entree that he eats, just solve for s:

510 = 45e + 30s

30s = 510 - 45e

s = (510 - 45e) / 30

s = 510/30 - 45e/30

s = 17 - 3/2e

This is the same as:

s = - 3/2e + 17