Table of Contents
To find the line of best fit on a TI-84 calculator, one must first enter the data into the calculator, then select the “Stat” option on the top bar and select “Calc” and choose either “LinReg(a+bx)” or “LinReg(ax+b)” depending on the data before pressing enter. The calculator will then display the equation of the line of best fit with the coefficients of the equation as well as the correlation coefficient (r) and the coefficient of determination (r-squared).
A line of best fit is the line that best “fits” the trend of a dataset.
This tutorial provides a step-by-step example of how to calculate the line of best fit for the following dataset on a TI-84 calculator:
Step 1: Enter the Data
First, we will enter the data values. Press STAT, then press EDIT. Then enter the x-values of the dataset in column L1 and the y-values in column L2:
Step 2: Find the Line of Best Fit
Next, we will find the line of best fit.
Press Stat, then scroll over to CALC. Then scroll down to LinReg(ax+b) and press ENTER.
Then press 2nd and 1 and comma , then press 2nd and 2 and comma , then press VARS and scroll over to to Y-VARS and press ENTER.
Your screen should look like this:
Press ENTER once more and the following line of best fit will be displayed:
The line of best fit is: y = 5.493 + 1.14x
Step 3: Plot the Line of Best Fit
Press ZOOM and then scroll down to ZOOMSTAT and press ENTER.
The following scatterplot with the line of best fit will be shown:
