Question

what does the y-intercept of the line tell you about the situation?
beth completely stopped 2 seconds after she started braking.
beth traveled 4 miles per hour slower every second.
beth was traveling 8 miles per hour 1 second after she started braking.
beth was traveling 12 miles per hour when she started braking.

Explanation:

The y - intercept of a linear model representing Beth's speed (y - axis) over time (x - axis, with x = 0 being when she started braking) gives the speed at the start (x = 0). So the y - intercept tells us her speed when she started braking. Among the options, "Beth was traveling 12 miles per hour when she started braking" matches this interpretation. The first option is about when she stopped (x - value related), the second is the slope (rate of change), and the third is a speed at x = 1, not the y - intercept.

Answer:

Beth was traveling 12 miles per hour when she started braking.