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Item 14Pavan is making monthly payments of $110 to pay a loan of $8140. The function f(x)=−110x+8140 represents the amount he owes after making x payments.What is the practical domain of function f?all real numbers from 0 to 8140all multiples of 110 between 0 and 8140all real numbers from 0 to 74all whole numbers from 0 to 74

User Henry H Miao
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The domain of the function is the set of "x" values that the function can assume. However, when we talk about practical domain, we want to take into consideration the use of the function. In this function, "x" is the number of payments He made. This means that:

- We can't have a negative number of payments, so "x" has to be positive.

- We can't make a fraction of a payment, so "x" must be a whole number.

- We can't make more payments than the amount necessary for the loan, so we can't have "x" greater than:


(8140)/(110)=74

Putting these into consideration, the practical domain of the function "f" is "All whole numbers from 0 to 74".

User Lxa
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