How to Draw a Tangential Line in Excel
- 1). Open the Excel spreadsheet with the data for which you want to draw the tangential line. A curved line graph is based on sets of two data points, for example time and amplitude.
- 2). Click and drag on the spreadsheet to select the data you want to show. Include the labels in your selection. Click on the "Insert" tab and then click on the down-arrow next to the "Scatter" button in the "Chart" area. Select "Scatter with Smooth Lines." The chart is created on your spreadsheet.
- 3). Click on the "Chart Tools: Layout" tab and then click the "Trendline" button on the right. Choose "Linear" to create a straight line that approximates the progress of the curved line. It will intersect the curve at some points.
- 4). Click on the "Insert" tab and then click "Shapes." Choose "Line" and draw the line so that it just touches one of the points on your curve.
- 5). Click on the "Drawing Tools: Format" tab and click the "Rotate" button on the right. Choose "More Rotation Options." Click the up or down arrow next to the "Rotation" field in the dialog box that appears to rotate the line on the curve. When the line is equidistant from both sides of the curve, click "OK."
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