1. The problem statement, all variables and given/known data A 2.1x10^3 kg car starts from rest at the top of a driveway that is sloped at an angle of 20 degrees with the horizontal. An average friction force of 4x10^3 N impedes the car's motion so that the car's speed at the bottom of the driveway is 3.8 m/s. What is the length of the driveway? 2. Relevant equations mass of car =2.1x10^3 kg velocity (final)=3.8 m/s average friction force= 4x10^3 driveway sloped at 20 degrees kinetic energy theorem=1/2m(vf)^2-1/2m(vi)^2 work formula=fd(cos θ) w=ke 3. The attempt at a solution If I log the numbers into the kinetic theorem equation ke=1/2(2.1x10^30)(3.8m/s)^2 If I log the numbers into the work equation w=4x10^3d(cos 20) and ke=w doesn't 4x10^3d(cos 20)=1/2(2.1x10^30)(3.8m/s)^2? If I simplify this, the distance is 4.03. Is there anything wrong with my equation?