How to Graph Inequalities Using the TI-83
- 1). Turn on your calculator. Press the "Y=" button (the upper-leftmost button on the calculator) to enter the function definition pane. Enter your function to graph in the first line. Remember to define your function in terms of X (button "X,t,o,n" will insert an X).
- 2). Use the arrow keys to move your cursor until it's on the leftmost character of the function (the cursor is the blinking, selected square). Move it left twice more and it will highlight the black diagonal line to the left of the character Y (the diagonal line is on the leftmost side of the screen).
- 3). Press "Enter" repeatedly to cycle through icons until you see one with a region of the icon shaded black. The icon that has the upper region shaded will cause the graph of that function to become a positive inequality (i.e., y > f(x)); the icon with the lower region shaded will cause the graph to be a negative, or lesser-than, inequality. Once you see the icon you want, just move the cursor out of that square -- there's no need to submit changes.
- 4). Press the "Graph" button in the same row as the "Y=" button you hit earlier. Watch as your calculator graphs the function and shades the area represented by the inequality.
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