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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**

Lastly, we will 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:

**Additional Resources**

How to Perform Linear Regression on a TI-84 Calculator

How to Perform Quadratic Regression on a TI-84 Calculator

How to Create a Residual Plot on a TI-84 Calculator