Question

Starting from 300 feet away, a car drives toward you. It then passes by you at a speed of 48 feet per second. The distance dd (in feet) of the car from you after tt seconds is given by the equation ​d=|300−48t|​d=|300−48t|. At what times is the car 60 feet from you?​

Answer 1

The answer to this question would be: 5 second

In this question, you are given the initial distance (300ft), car velocity(48ft/s) and the final distance(60ft). You are also given the equation to calculating the distance, so this question should be easier. The question is when the time where the distance is 60 ft. So the answer would be:

distance= 300-48t
60 = 300ft- 48t
48t= 300- 60=240
t= 5

Answer 2

we know that

The distance d (in feet) of the car from you after t seconds is given by the equation

$d=\left|300-48t\right|$

Find the times t for $d=60\ feet$

substitute the value of d in the equation

$60=\left|300-48t\right|$

Solve for t

There are two solutions

First Solution

$60=+(300-48t)$

$60=300-48t$

$48t=300-60$

$48t=240$

$t=240/48$

$t=5\ sec$

Second Solution

$60=-(300-48t)$

$60=-300+48t$

$48t=300+60$

$48t=360$

$t=360/48$

$t=7.5\ sec$

therefore

the answer is

At the time $t=5\ sec$ and at the time $t=7.5\ sec$