Find Speed of car based on stopping distance and decceleration.

[aprymek]

1. A car leaves skid marks 85 meters long. It slows down at a rate of 4m/s^2. How fast was the car traveling?
Again, totally confused. Don't know where to start.

 

[hage567]

You must show some attempt at working the problem to receive help. Could you explain what part is confusing you? What kinematic equations do you think would fit the information you are given?