A shape with 7 sides is called a heptagon.
Heptagon Definition
A heptagon is a two-dimensional closed polygon with exactly seven straight sides and seven angles. It’s sometimes also referred to as a "septagon" but "heptagon" is the standard term used in mathematics.
Regular and Irregular Heptagons
A regular heptagon has all sides and angles equal, while an irregular heptagon has sides and angles of different lengths and measures.
Properties of a Heptagon
- Number of sides: 7
- Number of angles: 7
- Number of vertices (corners): 7
- The sum of interior angles is 900∘900^\circ 900∘
- A regular heptagon has each interior angle measuring approximately 128.57∘128.57^\circ 128.57∘
- A heptagon has 14 diagonals
Name Origin
“Hepta” means seven in Greek, and “gonia” means angle, forming the word "heptagon." In Latin, “septagon” is also used but less commonly.
Quick Comparison Table
Shape Name| Number of Sides| Interior Angle Sum| Regular Angle
---|---|---|---
Heptagon| 7| 900° 46| 128.57° 46
A seven-sided polygon is always called a heptagon in geometry.
