A graph of the function y = 80x + 2 models Carli’s road trip, with her speed measured in miles per hour. The graph includes the two hours of stops she’ll make. Using this information, define which quantity describes the x-axis.

Answer 1

In the equation \( y = 80x + 2 \), where \( y \) represents Carli's total distance traveled in miles and \( x \) represents time in hours, the x-axis describes the total time of the road trip in hours, including both the time spent driving and the stops.

Since it is stated that there are two hours of stops included in the total time, the x-axis would represent the elapsed time in hours, which could extend beyond just the driving time, depending on how many hours she travels in addition to the stops. Thus, the quantity that describes the x-axis is "time in hours."