How to Configure and Enable Dual Display
1. Select the Apple Icon on the Finder menu on the top of the screen.
2. Select System Preferences…
3. Click on Displays
4. If everything is connected correctly, at this point both of your monitors should be operational and you should see a window similar to this one on each of them:
5. In order to change the arrangement of the dual monitor set-up click on the “Arrangement” tab: