Accurately construct a heptagon with our simple guide
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A regular heptagon (also called septagon) is a polygon with seven equal sides and seven equal angles.[1] Accurately constructing polygons is an important part of geometry, and for regular heptagons there are multiple ways to draw one. Here is the easiest method if you are using a straight edge and compass.
Steps
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1Draw an arbitrary circle, centred at a point . Keep in mind that you will need some extra space around the circle for construction lines.[2]
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2Draw the radius .[3]Advertisement
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4
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6Use your compass to trace the distance BD around the circle. You should end up exactly where you started. There is an error of about .2% for this method, which is negligible for any heptagon that fits on a regular A4 piece of paper. If you don't end up exactly where you started, there were probably some inaccuracies with the construction tools (e.g. the thickness of the pencil).[7]
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7Connect adjacent vertices.
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8Erase the construction lines if needed.
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Tips
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Put a piece of cardboard or a book under your paper so your compass doesn't slip.Thanks
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Sharpen your pencils before beginning, for increased precision.Thanks
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Trace over with a pen so it is easier to see.Thanks
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Warnings
- Since 7 cannot be written as the product of a power of two and a Fermat prime, it is impossible to do an exact compass and straightedge construction of a heptagon.[8] However, the above method has an error of less than 0.2%. When the circumscribed circle of the heptagon has a radius of 1 meter, there will be an error of approx. 1.7 mm.Thanks
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Things You'll Need
- Paper
- Compass
- Straight edge
- Pencil
- Pen
- Eraser
References
- ↑ Zina Savva. Mathematics Educator. Expert Interview
- ↑ https://www.youtube.com/watch?v=cErccoHui9g
- ↑ https://www.youtube.com/watch?v=EdtP9-fwg3o
- ↑ https://www.youtube.com/watch?v=EcR8c4obos4
- ↑ http://hptgn.tripod.com/heptagon.htm
- ↑ http://hptgn.tripod.com/heptagon.htm
- ↑ http://hptgn.tripod.com/heptagon.htm
- ↑ Zina Savva. Mathematics Educator. Expert Interview
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