Question

How do you find the equation of a regression line with a TI-83?

Answer 1

Enter the data into two lists first.

Explanation:

I will use brackets to indicate a button on the calculator and ALL CAPS to indicate what function to use.

Let X and Y be your two variables, corresponding to a collection of points.
Press [STAT] and then choose EDIT or press [ENTER].
This will open up the lists where you will enter the data.

Enter all of the values for X in list 1, one by one. Put a value in, then press [ENTER] to move down to the next line.
Now enter all of the values for Y into list 2 the same way.

Now press [STAT] again.
Use arrow keys to move to the CALC list of functions.
These are statistical calculations.

Choose item [4], which is labeled LinReg(ax + b).
That is, this is the Linear Regression function of the TI-83.

On the next screen, type
[2nd] [1] [,] [2nd] [2].

Notice that you need the comma button.
This tells the calculator which lists you will be using for regression. [2nd] [1] means List 1, for example.

Then press [ENTER], and voila!