
How to construct a heptagon, a regular 7sided polygon?


As stated in the constructions page, a heptagon can not be constructed by (strict) rulerandcompass rule. The practical way to do it is using the coordinates of the angular points and draw it as accurately as needed.
Here are the coordinates, for the orientation as shown: 
X  Y 
1.0000  0.0000 
0.6235  0.7818 
–0.2225 
0.9749 
–0.9010 
0.4339 
–0.9010 
–0.4339 
–0.2225 
–0.9749 
0.6235 
–0.7818 

For different orientations, manipulate x and yvalues, as follows:
 for a heptagon pointing to the left, exchange + and – of all values
 for a heptagon pointing up, exchange x and yvalues
 for a heptagon pointing down, do both, exchange + and –, and exchange x and yvalues
The given coordinate values assume a circumscribed circle with radius 1.0000. For heptagons of different sizes, multiply all x and yvalues with the desired radius of the circumscribed circle.


