The domain and function in this situation is
The domain is [0, 5]
The range is [0, 480]
How to find the domain and range
The domain of a function is the set of all possible input values. In this case, x represents the number of monthly payments.
The range of a function is the set of all possible output values. Here, the function represents the remaining loan balance after x monthly payments.
The possible x values for y = 0 (when the loan is fully paid)
0 = 480 − 96x
96x = 480
x = 480 / 96
x = 5
Since the student can make any non negative integer number of monthly payments, the domain is [0, 5]
The range starts from 480 to 0