INSTRUCTIONS TO MAKE A BEST-FIT LINE IN EXCEL
1. Enter in your data into a table format, with titles on the top of the column. Put the x-value in the left column and the y-values in the right column.
2. Highlight the
entire table, including titles, and then click on the chart wizard button.
3. Go through the steps. Step 2: Click "Next"
4. Step 3 you can label your axes and name your chart.
5. Step 4: Choose "Finish"
TO CREATE A BEST FIT LINE
1. Once you have your chart created, place your pointer over one of the data points and "Right Click"
2. Choose "Add a Trendline"
3. In the display box that appears, choose "Linear" and then go to options and click on the box to the left of "Display Equation on Chart" and "Display R-squared value on chart." Also if you want the y-intercept to be 0 click on that box.
4. Finally, click on "Finish" and then touch up the graph to make it look nice.
5. To lengthen the trendline on your graph, double click on the trend line and select the "options" and then use "Forecast" to make the line extend forward or backwards.
Borrowed from: http://www.bishopmoore.org/Mitchell/06-04-02%20MCM%20Web%20Page/excelgraphing.htm