Question 4 (Multiple Choice, Worth 2 points)

Linear Functions in the Real World

The number of miles, [tex]m[/tex], remaining on a family's trip can be modeled by the function [tex]m = -58x + 700[/tex], where [tex]x[/tex] represents the number of hours driven. How many hours have they driven if there are 350 miles remaining? Round the final answer to the nearest whole number.

A. 6 hours
B. 4 hours
C. 11 hours
D. 12 hours



Answer :

To solve for the number of hours, [tex]\( x \)[/tex], when the miles remaining, [tex]\( m \)[/tex], is 0, follow these steps:

1. Given the equation for the miles remaining:
[tex]\[ m = -58x + 700 \][/tex]

2. Set [tex]\( m \)[/tex] to 0, because we want to find out when there are no miles remaining:
[tex]\[ 0 = -58x + 700 \][/tex]

3. To isolate [tex]\( x \)[/tex], first move the 700 to the left side by subtracting 700 from both sides:
[tex]\[ -700 = -58x \][/tex]

4. Now, we need to solve for [tex]\( x \)[/tex]. Divide both sides of the equation by [tex]\(-58\)[/tex]:
[tex]\[ x = \frac{-700}{-58} \][/tex]

5. When you carry out the division:
[tex]\[ x = 12.0689655 \][/tex]

6. Round this result to the nearest whole number:
[tex]\[ x \approx 12 \][/tex]

Thus, the number of hours when the miles remaining is 0 is approximately 12 hours.

The correct answer is:
- 12 hours