Statistically speaking, if you’ve held a graphing calculator, it was probably made by Texas Instruments. The TI-89 Titanium continues this legacy with more memory, more pre-installed ...

Press the TI-89's "Mode" key. Press the down arrow on the calculator's directional keypad until the display shows "Exact/Approx." Press the right arrow until your desired mode choice is selected.

In 1990, Texas Instruments created its first graphing calculator, dubbed the TI-81, for use by students in high school math classes.