Can you find triangles on a 9-point circle? Can you work out their angles?
Join pentagons together edge to edge. Will they form a ring?
Draw some stars and measure the angles at their points. Can you find and prove a result about their sum?
Interior angles can help us to work out which polygons will tessellate. Can we use similar ideas to predict which polygons combine to create semi-regular solids?
Semi-regular tessellations combine two or more different regular polygons to fill the plane. Can you find all the semi-regular tessellations?
Draw some quadrilaterals on a 9-point circle and work out the angles. Is there a theorem?
Why does this fold create an angle of sixty degrees?
Is it possible to find the angles in this rather special isosceles triangle?
Given an equilateral triangle inside an isosceles triangle, can you find a relationship between the angles?
An equilateral triangle rotates around regular polygons and produces an outline like a flower. What are the perimeters of the different flowers?
