Medieval stonemasons used this method to construct octagons in a given square window.

Open your compasses to a radius of half the diagonal of the square and construct an arc with centre one vertex of the square - mark the two points where the arc crosses the sides.

Do that for all 4 vertices of the square giving 8 points which are the vertices of an octagon.

Is the octagon regular?

Can you prove it?

Enrichment Task

Last change to this page
Full Page history
Links to this page
Edit this page
  (with sufficient authority)
Change password
Recent changes
All pages