If you are interested in filling the display, check out this how to from google:
Change the size of your slides
- Click the File menu and select Page setup.
- Select a size from the dropdown menu. You can select from several options:
- Standard (4:3)
- Widescreen (16:9)
- Widescreen (16:10)
- Custom — If you select Custom, you can specify the dimensions of your slides, selecting the units (inches, centimenters, points, or pixels) from the drop-down menu.
- Click OK.
Link from Google: https://support.google.com/drive/answer/3447672?hl=en