Trying to network my Mac w/Verizon FiOS & AirPort Extreme

Ok, so to start with I'm new and don't really know too much. So, with that in mind, my land lord just upgraded our internet to Verizon FiOS. It works great and I can pick up the wireless signal on my Mac Book Pro. Now, my issue is that I also have a PowerPC G4 that does not have a wireless card in it. So I am trying to use my Airport Extreme router to recieve the wireless connection so that I can get this computer online. Is that possible? Please let me know how or if you need any more information let me know and I can try to get it. Thank you very much for any help.

Brandon