Can you hook two amps together and get one combined power?

If you mean in series (the output of amplifier a plugs into the input of amplifier b), probably not. Unless amp b can handle the input power delivered by amp a, and then linearly amplify that signal up to its own level, you will get massive distortion. If you've ever heard an Electric Guitar in maximum overdrive mode, you have a sense of what will happen.

The way to do this is give each amp 1 speaker and y-cord the INPUT of each amp.