A car with 5,000 miles is purchased. The car averages 30 miles per gallon. The linear function [tex]m(x) = 30x + 5,000[/tex] models the total mileage on the car, where [tex]m(x)[/tex] is the total mileage and [tex]x[/tex] is the gallons of gas used. What is the range of the function?

A. [tex][0, \infty)[/tex]
B. [tex][5,000, \infty)[/tex]
C. [tex](-\infty, 5,000)[/tex]
D. [tex](-\infty, \infty)[/tex]



Answer :

To determine the range of the function [tex]\( m(x) = 30x + 5,000 \)[/tex], let's analyze the function step by step.

1. Understanding the Function:
- The given function [tex]\( m(x) = 30x + 5,000 \)[/tex] represents the total mileage on the car.
- Here, [tex]\( m(x) \)[/tex] is the total mileage and [tex]\( x \)[/tex] is the number of gallons of gas consumed.

2. Interpretation of the Function:
- When [tex]\( x = 0 \)[/tex], the initial mileage of the car is given by [tex]\( m(0) \)[/tex]:
[tex]\[ m(0) = 30 \cdot 0 + 5,000 = 5,000 \][/tex]
So, the car starts with 5,000 miles.

- As [tex]\( x \)[/tex] increases (i.e., more gas is consumed), the mileage [tex]\( m(x) \)[/tex] will also increase because [tex]\( 30x \)[/tex] is a positive term.

3. Identifying the Range:
- Because the function [tex]\( m(x) = 30x + 5,000 \)[/tex] is linear with a positive slope (30), it means that as [tex]\( x \)[/tex] increases from 0 to positive infinity, [tex]\( m(x) \)[/tex] will increase from 5,000 to positive infinity.
- The lowest value of [tex]\( m(x) \)[/tex] occurs at [tex]\( x = 0 \)[/tex], which is 5,000.

Thus, the set of all possible values of [tex]\( m(x) \)[/tex] starts from 5,000 and increases indefinitely. This means that the range of the function can be expressed as:

[tex]\[ [5,000, \infty) \][/tex]

Therefore, the correct answer is:

[tex]\[ [5,000, \infty) \][/tex]