Using the ti 83, ti 83 plus, or ti 84 to graph quadratic inequalities

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The graphing calculator can be a great
checking tool or a fast way to answer a
multiple choice question.
Example – suppose you graphed the
following and wanted to check your answer:
x  2x  3  0
2
Turn on your calculator and input the
expression into the Y= menu
To enter an inequality symbol, press the 2nd key and
then the MATH button:
Scroll down to option 3 “>” and press enter
Press the zoom button and choose option 6
Here’s what we should get:
The graph tells us our solution set is a disjunction of
x = -1 and x = 3
x  1
x3
The calculator does not tell us whether or not to use
open or shaded circles. We have to look at the
inequality to determine this.
Another problem might be that you see nothing after
you press the graph button. Try changing the
window.
Are you getting the following error message?
This means that your calculator is trying to plot
something that is not defined. This is a simple fix.
Go back to the Y= menu
One or more of the plots are turned on. On my
calculator, I have Plot1 turned on. To turn it off,
scroll up to the Plot(s) that are on and press ENTER
to turn them off.
Once all of the plots are turned off, it should graph
like normal.
Are you getting this error message?
Easiest way to fix this is to press the ZOOM button
the choose option 6 and it should graph normally
If you are getting a SYNTAX error, make sure you
enter the inequality/equation correctly
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