4K How to draw pentagon with using a compass and a ruler

This video is about drawing pentagon by hands with using a compass and a ruler. Attention! If you need to do this quickly in practice, the following two different ways are more effective:
1. Make it with a protractor
2. Make a calculation of the side of the pentagon A=1,17557*R
A - pentagon side, R - outer circle radius
this is quick and does not require any construction.
The coefficient 1,17557 is calculated from this equations A=2*R*sin(180/n),
n - the quantity of sides of the polygon. This way you can build any polygon using a ruler with divisions.
There are also other construction methods.

Видео 4K How to draw pentagon with using a compass and a ruler канала Pavel Kubarkov