TI-84 documentation

How to Graph Functions on a TI-84 Calculator

Enter an equation, choose a useful viewing window, draw the graph and inspect important points.

Enter an equation, choose a useful viewing window, draw the graph and inspect important points.

1Enter a function correctly
2Choose a useful graph window
3Trace intercepts and turning points

1. Enter the function

Press Y=. Move to Y1 and enter X^2-4. Use the calculator's X,T,θ,n key for the variable.

Y=X,T,θ,n4
Y1 = X² - 4

2. Set a standard window

Press WINDOW and use Xmin = -10, Xmax = 10, Ymin = -10 and Ymax = 10. This range is a useful starting point for many algebra graphs.

3. Draw the graph

Press GRAPH. You should see an upward-opening parabola whose lowest point is near (0,-4).

Expected result: the curve crosses the x-axis near x = -2 and x = 2.

4. Trace important points

Press TRACE, then use the left and right arrow keys. The coordinate readout gives approximate x- and y-values. For exact zeros, use 2nd → TRACE (CALC) → zero.

Worked example: locate the right x-intercept

  1. Open the CALC menu with 2nd → TRACE.
  2. Select zero.
  3. Move the cursor to the left of x = 2 and press ENTER.
  4. Move to the right of x = 2 and press ENTER.
  5. Move near the crossing and press ENTER for the guess.
Expected result: x = 2 and y = 0, allowing for display rounding.

Troubleshooting

Blank graph

Check that the equals sign beside Y1 is highlighted and reset with ZOOM → 6:ZStandard.

Wrong trig shape

Confirm whether the problem expects Degree or Radian mode.

Graph looks flat

The y-range may be too wide. Reduce Ymin and Ymax.

Unexpected vertical lines

Discontinuities may be joined visually. Inspect with TRACE and TABLE.

Practice

Graph Y1=2X+3. Predict the y-intercept before pressing GRAPH.

Reveal the answer

The line crosses the y-axis at (0,3) and has slope 2.

Practice with the calculator open

Use the guide in one tab and the calculator in another.

Open TI-84 Calculator

Editorial note: This guide is independently written for classroom practice and was reviewed against the TI-84 Plus CE guidebook. Button labels and menu availability can vary by model and operating-system version.

Last reviewed: July 17, 2026
Learning standard: worked example, expected result, troubleshooting and practice.

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