1. The problem statement, all variables and given/known data A ball of mass 20.0kg (mass A) traveling at a initial speed of 5.0m/s, collides with a ball of mass 10.0kg (mass B) which was traveling at a initial speed of 1.0m/s. What is the final velocity of mass A, what is the final velocity of mass B? mA = 2mB 2. Relevant equations ΣFext = 0 Δp = 0 ΔEk = 0 quadratic equation 3. The attempt at a solution I am unsure how to find the final velocities here because I have two variables and I have to use the quadratic equation to find the final velocities right? So I was just wondering if I could somehow isolate and get rid of a variable, this is what I have so far: Δp=0 PiA + PiB = PfA +PfB mAviA + mBviB = mAvfA + mBvfB mAviA + 2mAviB = mAvfA + 2mBvfB viA + ViB = vfA + vfB (5.0) + (1.0) vfA + vfB 6.0-vfA = vfB Then I put it into the kinetic energy equation and put in all the numbers and I got as an answer: 510.0 = (20.0)(vfA)(squared) + (10.0)(vfB)(squared) My question is basically how am I supposed to incorporate this into the quadratic equation to find the final velocities?