Regular polygons and circles

The sides of a triangle are 25, 39 and 40 units of length. Find the diameter of the circumscribed circle.

Follow instructions to fold sheets of A4 paper into pentagons and assemble them to form a dodecahedron. Calculate the error in the angle of the not perfectly regular pentagons you make.

Remember that you want someone following behind you to see where you went. Can yo work out how these patterns were created and recreate them?

This LOGO challenge starts by looking at 10-sided polygons then generalises the findings to any polygon, putting particular emphasis on external angles

Recreating the designs in this challenge requires you to break a problem down into manageable chunks and use the relationships between triangles and hexagons. An exercise in detail and elegance.

See if you can anticipate successive 'generations' of the two animals shown here.

In LOGO circles can be described in terms of polygons with an infinite (in this case large number) of sides - investigate this definition further.

Can you use LOGO to create this star pattern made from squares. Only basic LOGO knowledge needed.

Use the isometric grid paper to find the different polygons.

Sally and Ben were drawing shapes in chalk on the school playground. Can you work out what shapes each of them drew using the clues?