How to Start and Quit Inequality Graphing on the TI-84 Plus
The Inequality app on your TI-84 Plus calculator is a powerful mathematics tool. To start the Inequality app, press [APPS]. See the first screen. Then, press [ALPHA][x2] if necessary, use the down-arrow key to move the cursor to the Inequalz app, and press [ENTER] to select the app.
In the list of apps, this app is titled, Inequalz. However, the official name of the app is the Inequality Graphing app. After choosing the app, you are confronted with one of the last two screens shown here.
If no other apps are running, you see the second screen. Press any key to enter the Inequality Graphing app. If Inequality Graphing is already running, you see the third screen. Press  to re-enter the app.
After you enter Inequality Graphing, you are placed in the Y= editor so that you can enter functions and inequalities. The functions previously housed in this editor appear on the screen along with the inequality symbols at the bottom of the screen, as illustrated in the first screen.
If you move the cursor so that it is not on an equal sign, the inequality symbols at the bottom of the screen vanish, as in the second image in this figure.
On the TI-84 Plus C, Context Help in the border at the top of the screen says, “Select Relation – Press Alpha f1–f5.” If you forget a step while using this app, use the Context Help to guide you!
Most of the time, you don’t even know the Inequality Graphing app is running unless you are actively using the app or unless you place the cursor on an equal sign in the Y= editor to display the inequality symbols, as in the first screen. How to quit the app is about as puzzling as knowing whether or not it is running.
To quit (exit) this app on the TI-84 Plus C, press [Y=] to access the Y= editor. Use the arrow keys to move your cursor to “Quit-App,” located in the top-right part of the screen as shown in the first image. Press [ENTER] and the second screen appears. Press  to quit the app. On the TI-84 Plus, press [APPS] choose Inequalz and press  to quit the app.