A linear equation is drawn as a straight line on a set of axes. To draw the graph we need coordinates. We generate these coordinates by substituting values into the linear equation.

Open the Excel workbook that contains the chart whose trend-line equation you want to access. Press "Alt-F11" to open Excel's Visual Basic Editor.

How to Find the Slope of a Line on an Excel Graph. In math and statistics, you may occasionally need to calculate the slope of a line generated by coordinates in the (x,y) format.