mp.mathematical physics – How to calculate Angle of Motion between two Points in 2D?

I am currently making a 2D Game and I want to shoot a Hook with a specific Power X into the direction of my Mouse, so I need to find out the Angle of Motion that the Hook has to shoot, here is an illustration of what I mean:

illustration

so if anyone could help me with some maths on how to calculate this i would be very happy