**1. The problem statement, all variables and given/known data**

A car level on ground, starting from 15m/s, decelerates uniformly to rest in 20 seconds. What distance does the car cover while decelerating?

**2. Relevant equations**

Vf = Vi+at

Vf^2=Vi^2+2aX

X=Vit+(1/2)at^2

X = Distance

Vf = Final velocity

Vi = Initial velocity

a = acceleration

t = time

**3. The attempt at a solution**

I started with the X=Vit+(1/2)at^2 formula and attempted to plug in the numbers but I have no idea how to find acceleration. I mean, I know acceleration is Δv over Δt but how am I supposed to find the final velocity when I need the acceleration to plug in the formula? I’ll admit I zoned out a little in my last class because I was tired from work the day before.

http://ift.tt/1kxsVXT