- #1

chroncile

- 35

- 0

## Homework Statement

A truck travels at a constant speed of 28.0 m/s in the fast lane of a two-lane highway. It approaches a stationary car stopped a the side of the road. When the truck is still 125 m behind the car, the car pulls out into the slow lane with an acceleration of 2.6 m/s2. How long will it take the truck to reach the car? (Answer is 6.32 s)

## Homework Equations

d

_{t}= d

_{c}+ 125

d

_{c}= 1.3t

^{2}

## The Attempt at a Solution

Okay I got the answer, but it's in quadratic form so:

1.3t

^{2}- 28.0t + 125 =

t = 15.2 s or t = 6.32 s

How do you know which answer is the correct one?