1. The problem statement, all variables and given/known data (It includes a diagram so I'm just going to link it) #22 from Chapter 7 of the People's Physics Book (second to last page, with the table) http://scipp.ucsc.edu/outreach/07Momentum.pdf 2. Relevant equations p(i)=p(f) p(f)x=m*v*cosin(theta) [I "made these up", so to speak, but it seems logical] p(f)y=m*v*sin(theta) 3. The attempt at a solution The main trouble I am is with b), finding the actual direction of the 2 kg ball. First, however, I wanted to verify my steps so far is correct... The initial momentum should be 8kg*m/s by summing the individual, positive momentums of each ball. For the final momentum of the 3 kg ball, I obtained them like so... We know the angle is 30 degrees and it has a velocity of 1 m/s, so we know Momentum in the x direction = 3kg*1m/s*cosin(30) = 1.50 Momentum y = 3kg*1m/s*sin(30) = 2.60 So now I set up our conservation equation like so... 8 kg*m/s = (1.50+2.60)kg*m/s + p(2kg ball) Is this correct so far?