Final answer:
The velocity of the wedge is 6.0 m/s to the right.
Step-by-step explanation:
The wedge and block system can be considered as one object, since they are in contact and move together. The vertical component of the block's velocity is 3.0 m/s, and the horizontal component is 6.0 m/s. This means that the block is moving downward towards the right.
Since the wedge and block move together, the velocity of the wedge is also 6.0 m/s to the right.