Question

Jim runs a coffee delivery service. His income can be measured using the function y=3x+27, where y is his income and x is the number of cups of coffee he delivers. What is a reasonable domain and range for the function in this situation?

Answer 1

A reasonable domain is all values more than 0.

Explanation:

If x is the number of cups of coffee, and y is his income, a reasonable domain is all values more than 0.

Because, a function domain refer to all x values that such function can use. In this case, all values have to be positive, because we cannot sale -2 cups, and they have to be more than 0, because he deliver at least one cup, let's say that x = 0 is trivial solution.