Answer:
Ball A will move towards West with speed 8 m/s
Ball B will move towards East with speed 12 m/s
Step-by-step explanation:
As we know that during collision there is no external force on the system
So here we can use momentum conservation for finding the final velocities of two balls
so we have

since two balls are identical so we have



also we know that for elastic collision we have

so we have


so we have
Towards East
Towards West