Start GeoMaster on the TI-84 Plus Calculator
When you start the geometry application GeoMaster on the TI-84 Plus calculator, you see the version number on the screen. If that number is smaller than 1.10 for GeoMaster, check out Texas Instruments’ website to see if there is a more recent version for you to download.
To start GeoMaster, press [APPS][ALPHA][TAN] if necessary use
to move the cursor to the GeoMaster application, and press [ENTER] to select the application. You are confronted with one of the three screens.
If no other applications are running, you see the first screen. Just press any key to enter the GeoMaster application. If GeoMaster is already running, after you press [APPS], you see the second screen. Press  to re-enter the application. The third screen tells you that another application is currently running.
Press  to exit that application, and then press any key to enter GeoMaster. After you enter GeoMaster, you are confronted with one of the two screens.
When you enter the GeoMaster application, you usually see the first screen. But if you re-enter GeoMaster while it is still running, you see the screen as you left it but without the menus at the bottom of the screen, as in the second screen. To reinstate the Menu headings at the bottom of the screen, press [GRAPH] or [ALPHA].
If you press a menu key such as [MODE], [STAT], [MATH], or [VARS] while GeoMaster is running, you are sent to that menu while GeoMaster continues to run in the background. The same thing happens when you press [Y=], [WINDOW], or [ZOOM] when the Menu bar is not at the bottom of the GeoMaster screen. To re-enter the GeoMaster application, just press [GRAPHS] or [APPS].