Can you confirm a simple Physics Velocity Question?

1. The problem statement, all variables and given/known data

Object a Mass 6kg moving velocity 5m/s is followed by a second object mass 8kg velocity 8m/s in the same straight line.

If the two objects are joined together after collision and move in the original direction, calculate heir common velocity.

3. The attempt at a solution

Now have either:

6x5 - 8x8 = 14V

-34 = 14V

-34/14 = V

V = -2.42m/s

or 5x6 + 8x8 = 14V

94 = 14V

94/14 = V

V = 6.71m/s

Which one is right?

Thanks in advance
 
The second one is right because both of the objects are moving in the same direction hence you would ADD the initial momentum of each mass.
 

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