Connecting Realtik Audio Speakers to computer

There is no place to plug it to my computer. I have plugged the green and orange wire to the computer and the wall plug but can't figure out where to plug in the other pronged plug. HELP
 
I could not find Realtik Speakers on Google. You did not mention your computer make/model. There are few audio speaker standards. I suggest (to everyone) please include all possible information at your disposal to help us provide satisfactory answers.