Is Momentum Conserved in a Collision Between Two Unequal Masses?

[lucy bolt]

Ball A, which weighs 2 kilograms, is moving at 0.5 meters/second and strikes stationary Ball B at the direct center of the ball.
Ball B, which weighs 3 kilograms, moves off at 0.3 meters/second and in the same original direction Ball A was moving. Ball A continues to move forward, but only at 0.1 meters/second. Is momentum conserved? Explain.I don't even know where to start, or what to do so could I have some help with this?

 

[physics user1]

The momentum of the system is conserved if it's the same before the strike and after...
What's the momentum before?
What about after?

 

[Irene Kaminkowa]

The system consists of two bodies: ball A and ball B
All the movements are performed along one axis: OX. Let the positive direction coincide with the direction of ball A movement.
Then, the momentum before the strike
P₁ = m_Av_A + m_Bv_B
v_A = 0.5 m/s, v_B = 0
The momentum after strike
P₂ = m_Au_A + m_Bu_B
u_A = 0.1 m/s, u_B = 0.3 m/s

So, the conclusion is clear but still up to you)