Pentagon – Properties
- In a pentagon the sum of the internal angles is equal to 540°.
- In a regular pentagon each interior angle measure is 108°, and each exterior angle measure is 72°.
- A regular pentagon has five axes of symmetry, each one of them passes through a vertex of the pentagon and the middle of the opposite edge.
- All diagonals of a regular pentagon are equal to each other.
- It is a regular pentagon, if all the sides are equal and all the angles are of equal measure, otherwise it is irregular.
- All diagonals of a pentagon form a pentagonal star called pentagram. A pentagon can be divided into three triangles.
- Five equal sides make up an equilateral pentagon.