Velocity of Car & Truck After Collision: Solved

[Weezergames]

Homework Statement

A 1200kg car moving at 8m/s to the right strikes a 2000kg truck moving at 4m/s to the left. Afterwards the velocity of the car is is 6m/s to the left. What is the velocity of the truck?

Homework Equations

The Attempt at a Solution

 

[Carid]

You are supposed to make some attempt at the question before asking for help!

 

[Dell]

you need to specify how much energy is lost in the collision