It is known that the sum of the exterior angles of a convex polygon is always 360º. Since an exterior angle of a right angle is also a right angle, our four right angles would take up the entire 360º ...

Learn about and revise angles, lines and multi-sided shapes and their properties with this BBC Bitesize GCSE Maths Edexcel study guide.

Learn how to apply formulae for the interior and exterior angles of a polygon and how to create tiling patterns and tessellations with this GCSE guide.

We’ll stick with “convex” polygons, those whose interior angles are each less than 180 degrees, and we’ll allow ourselves to move them around, rotate them and flip them over.