TI-83 Resource Website -- Graphing Basics -- Using the ZERO Command

TI-83 Resource Website

Graphing Basics

Using the ZERO Command

The ZERO command calculates the x-intercept of a function.

Example: Find the value for f(x) = 4x + 8

Step 1: Graph the function using the steps from Graphing a Function.

Step 2: Press 2nd (yellow button), CALC (above the blue menu button TRACE). Using the blue down arrow, select 2: zero.

Step 3: Press ENTER. The graph of the function will appear. Note that "Left Bound?" is in the lower left hand corner. Using the left and right blue arrow buttons, position the cursor below the x-axis (horizontal axis). Note that you can position the cursor anywhere below the x-axis just as long as it is clearly below the x-axis.

Step 4: Press ENTER. Again, in the lower left hand corner, "Right Bound?" appears. Using the left and right blue arrow buttons, position the cursor above the x-axis (horizontal axis). Note that you can position the cursor anywhere below the x-axis just as long as it is clearly above the x-axis.

Step 5: Press ENTER. In the lower left hand corner, "Guess?" appears. Using the left and right blue arrow buttons, position the cursor as close to the x-intercept as possible.

Step 6: Press ENTER. The x-intercept should appear on the bottom of the screen.

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This site is maintained by Donna L. Sperry

Step 1: Graph the function using the steps from Graphing a Function.
Step 2: Press 2nd (yellow button), CALC (above the blue menu button TRACE). Using the blue down arrow, select 2: zero.
Step 3: Press ENTER. The graph of the function will appear. Note that "Left Bound?" is in the lower left hand corner. Using the left and right blue arrow buttons, position the cursor below the x-axis (horizontal axis). Note that you can position the cursor anywhere below the x-axis just as long as it is clearly below the x-axis.
Step 4: Press ENTER. Again, in the lower left hand corner, "Right Bound?" appears. Using the left and right blue arrow buttons, position the cursor above the x-axis (horizontal axis). Note that you can position the cursor anywhere below the x-axis just as long as it is clearly above the x-axis.
Step 5: Press ENTER. In the lower left hand corner, "Guess?" appears. Using the left and right blue arrow buttons, position the cursor as close to the x-intercept as possible.
Step 6: Press ENTER. The x-intercept should appear on the bottom of the screen.