A linear equation is a formula that expresses a series of values of one axis (y) in terms of the other axis (x). Because Microsoft Excel 2007 deals with both formulas and graphs, you may use the program to graph any linear equation. First, enter the parameters of the graph. To do this, create a table of x and y values, determining the range of your x axis, and enter the formula (in the form of y=mx + b, in which "m" equals the line's slope and "b" is the yaxis intercept). Excel will calculate the values of y for each value of x according to the formula. Then you'll be able to set up a graph to display the values.
Things You'll Need
 Microsoft Excel
 Linear equation

Open a new document in Microsoft Excel 2007.

Enter "x" in the top left cell. Press "Tab" and enter "y" in the next cell over.

Enter a series of values in the first column under "x" (cells A2 and down). These values will make up the parameters of the horizontal axis. For instance, enter "5" in cell A2. In the next cell down, enter "4" and onward: 3, 2, 1, 0, 1...all the way up to 5.

Define the name of the x values so you can enter the formula for the "y" column. Use your cursor to highlight the cell values in column A. In other words, highlight cell A2 and drag your cursor down to the last cell in column A. Click the "Formulas" tab. In the "Defined Name" group, click "Define Name." Enter "x" in the "Name" field and click "OK." This tells Excel that all the numbers in column A are equal to a value of x.

Enter a linear equation in cell B2. The equation will appear in the Formula Bar. With the format y=mx + b, type "=m*x + b." When you go to a new cell, Excel will calculate the result of the formula, which will now appear in the cell.

Copy the formula you entered is Step 5 to the other cells in column B. Select cell B2, which contains the formula. Click the "Home" tab. Under "Clipboard," click the "Copy" icon. Highlight all the cells below B2. In the "Clipboard" group, click "Paste." Select "Formulas." This will add the formula to each cell. You'll now see the yvalue for each corresponding xvalue.

Select all the cells to begin making a graph for the data.

Click the "Insert" tab. Click the type of chart you want in the "Charts" group. For the purpose of making a linear graph, choose "Scatter." This will plot the x and y values against each other. Choose the chart subtype you want. To show a simple line graph with your data points, click the "Scatter with Smooth Lines and Markers" icon.

Click the chart to display the "Chart Tools" tabs. Use the "Design" tab to change the chart's layout and style. Click the "Layout tab to make modify the position of title and axis labels. Select the graphed line and click the "Format" tab to adjust shape styles.

Click the "Microsoft Office Button," and click "Save as" to save the data and graph.
References
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