Can you help me solve this

Two blocks are sliding toward each other along a horizontal frictionless tabletop. One block has a mass of 3.2 kg, and it is sliding to the right with a speed of 9.5 m/s. The other block has a mass of 4.2 kg, and it is sliding to the left with a speed of 2.8 m/s. The two blocks then collide head-on and stick together. What is the speed of the combined block after the collision