How to Find the Equation of a Trendline in Excel- 5 Steps

What Is Trendline in Excel?

A trendline is a linear or curved line in a graph or chart that defines the general pattern of the selected dataset. It is also referred to as the line of best fit.

To find the equation of a line:

Step 1- Prepare Dataset

Create a dataset with information of Item Name, Sold Items, and Sales amount of 6 types of fruits (here).

How to Find the Equation of a Line in Excel

The values in columns C and D act as Y and X axis.

Step 2 – Create a Scatter Chart

Select C5:D10.

How to Find the Equation of a Line in Excel

Go to Insert and select Scatter Chart in Charts.

Choose Scatter.

You will see the chart.

Step 3 – Add a Trendline to the Chart

Select the chart.
Click the Plus (+) icon to open Chart Elements.

How to Find the Equation of a Line in Excel

Check Trendline.

You will see a trendline.

Format the trendline:

Step 4 – Find the Equation of the Line

Select the line.
Right-click it and choose Format Trendline.

How to Find the Equation of a Line in Excel

In the Format Trendline panel, check Display Equation on chart.

The equation is displayed beside the line.

Step 5 – Add Decimal Places to the Equation

Select the trendline again.
Right-click it and select Format Trendline Label.

How to Find the Equation of a Line in Excel

Select Number in Category.

Enter a value in Decimal places.

Decimal points are displayed in the line equation.

How to Find the Slope of Line Equation in Excel

To get the slope of the equation, use the SLOPE function.

Select C12.
Enter this formula.

=SLOPE(D5:D10,C5:C10)

How to Find Slope of Line Equation in Excel

Press Enter.
The value of the slope for the line is displayed.

The SLOPE function was used to calculate the change rate between dependent and independent variables. D5:D10 defined the dependent data points on the Y axis. C5:C10 acts as the independent data points plotted on the X-axis.

Note: You can also apply the LINEST function to count the slope. Press Ctrl + Shift + Enter after inserting this formula. =LINEST(D5:D10,C5:C10)

Download Practice Workbook

Download the sample file.

Find the Equation of a Line.xlsx