How to Enter Inequalities in the X= Editor
You can use the X= editor in your TI84 Plus calculator to define some equalities and inequalities. Equalities and inequalities of the following form are defined in the X= editor the same way inequalities are defined in the Y= editor:
To access the X= editor, follow these steps:

If you are not currently in the Y= editor, press [Y=] to get there.

Repeatedly press the uparrow key until the cursor is on X= in the upperleft corner of the Y= editor.
This is illustrated in the first screen.

Press [ENTER] to access the X= editor.
The number N in the inequality can be entered as an arithmetic expression, as illustrated in the second screen. That expression is evaluated by the calculator after you press [ENTER], the uparrow key, or the downarrow key as illustrated in the third screen.
To return to the Y= editor from the X= editor, repeatedly press the uparrow key until the cursor is in the upperleft corner of the screen, and then press [ENTER].
When you exit the Inequality Graphing app, all entries made in the X= editor are erased.