Castle Learning Reference

Calculator Tips for Pre-Calculus

Creating a Scatter Plot with a Line or Curve of Best Fit

The following instructions apply to a TI83 or TI84 graphing calculator.

First follow the directions for how to create a regression up to step 3.

Enter the 'x' values into List 1 and the 'y' values into List 2.
To get to List 1 and List 2, use the following key strokes.

'stat'
enter at 'edit'
You should see the following screen:

**If there are numbers in the lists, clear the lists before inputting any other values.

Now enter the information into List 1 and List 2. Below is just an example:

Follow the key strokes below to find the type of regression the problem is asking for.

'stat' key
right arrow over to 'calc'
For a linear regression, hit '4'
For a quadratic equation, hit '5'
For an exponential function, hit '0'
For a power regression, hit 'A'

**These are the most common regressions. The example shows a linear regression (hit '4'). Below is the screen you will see.
Hit the 'vars' key
Right arrow over to 'y-vars'
Hit enter '3' times
The screen that you should see is:
Hit the 'y=' key. You should see the following screen.

**To graph the scatter plot, highlight "Plot 1". Arrow up to “Plot 1” and hit enter, then arrow back down.
Now to graph hit "zoom" and then '9' for “ZoomStat”. The following screen will appear.

**This is the scatter plot with the graph of the line of best fit.