It would not be practical to draw a 26-sided polygon, so the formula is more useful here. (26 – 2) × 180 = 24 × 180 = 4320. The interior angles of a 26-sided polygon sum to 4320°.

To see a four-sided polygon — a rectangle — look higher in the western sky close to the overhead zenith. The four brightest stars you see form a diamond, a diagonally orientated rectangle.

We’re at the Polygons annual party. It’s polygons only so to get a ticket, you have to be a 2D shape, with straight sides. Polygons can be grouped based the number of sides they have. So let ...

Learn more about how angles in an 𝒏-sided polygon add to 180° × (𝒏 – 2) with this BBC Bitesize Maths article. For students between the ages of 11 and 14.