A heptagon is a polygon that has actually seven political parties (Hepta- method seven). In the figure below are several varieties of heptagons.

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Heptagon classifications

Like other polygons, a heptagon have the right to be share as continuous or irregular. If every the sides and interior angles of a heptagon room equal, it is a continual heptagon. Otherwise it is an irregular heptagon.

Regular heptagonIrregular heptagon
All sides and also interior angles space equalNot every sides and angles space equal

Heptagons and other polygons can likewise be classified together either convex or concave. If all interior angles that a disappear are much less than 180°, the is convex. If one or an ext interior angles is bigger than 180°, it is concave. A regular heptagon is a convex heptagon. A concave disappearance is an rarely often rare heptagon.

Convex heptagonConcave heptagon
All internal angles 180°

Diagonals of heptagon

A diagonal is a heat segment joining two non-consecutive vertices. A full of fourteen distinct diagonals can be drawn for a heptagon. The following figure is an example.


There space 4 diagonals prolonging from every of the 7 vertices of the heptagon over creating a complete of 14 diagonals.

Internal angles of a heptagon

The amount of the inner angles the a heptagon equals 900°.


As shown in the figure above, 4 diagonals can be attracted to divide the disappear into five triangles. The blue lines over show simply one way to divide the heptagon into triangles; there are others. The amount of inner angles the the 5 triangles amounts to the amount of internal angles that the heptagon. Due to the fact that the amount of the interior angles the a triangle is 180°, the amount of the inner angles the the heptagon is 5 × 180° = 900°.

Regular heptagon

A continuous heptagon is a heptagon in which every sides have equal length and also all interior angles have equal measure.

Angles that a constant heptagon

Since every of the seven inner angles in a continuous heptagon room equal in measure, each inner angle measures 900° ÷ 7 ≈ 128.57°, as presented below.


Each exterior angle of a regular heptagon has actually an same measure that is roughly 51.43°.

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Symmetry in a constant heptagon

A consistent heptagon has 7 currently of symmetry and a rotational symmetry of stimulate 7, definition that it have the right to be rotated in together a method that it will certainly look the same as the initial shape 7 time in 360°.

Lines of symmetryRotational symmetry
7 present of symmetrySeven 51.43-degree angles of rotation about the center