How to Construct a Decagon
- 1). Decide if you want a regular or irregular decagon. If you want an irregular one, choose any 10 points on a circle and connect them with straight lines.
- 2). Draw the first side of the length you want. If you want a regular decagon, start by drawing one side.
- 3). Measure an angle of 144 degrees with the protractor.
- 4). Draw a line, of the same length as the first, on that angle. You will have an almost straight line.
- 5). Measure another 144 degree angle, bending in the same direction.
- 6). Draw another line of the same length at that angle.
- 7). Repeat steps 5 and 6 until you have drawn 10 lines and you are back where you began.
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