## How many diagonals are there in a polygon of 12 sides?

54

In a polygon of 12 sides, no. of diagonals n(n−3)2=12(12−3)2=12×92=54.

## What is the size of each interior angles of a regular polygon with 12 sides?

The total interior angle of a 12 sided polygon is = (12 – 2) 180 degrees = 1800 degrees. The internal angle at each vertex of an regular dodecagon is equal to = 1800 = 150 degrees. The total exterior angle of a 12 sided polygon is 360 degrees.

**What does a 12 sided polygon add up to?**

1800 degrees

So, the sum of the interior angles of a dodecagon is 1800 degrees. All sides are the same length (congruent) and all interior angles are the same size (congruent).

### What is a 12 sided prism called?

dodecahedron

The decagonal prism has 12 faces, 30 edges, and 20 vertices, so, it is a dodecahedron (while the term is usually applied to regular dodecahedron or rhombic dodecahedron.). If faces are all regular, it is a semiregular or prismatic uniform polyhedron.

### What is the polygon with 11 sides called?

In geometry, a hendecagon (also undecagon or endecagon) or 11-gon is an eleven-sided polygon. (The name hendecagon, from Greek hendeka “eleven” and –gon “corner”, is often preferred to the hybrid undecagon, whose first part is formed from Latin undecim “eleven”.)

**Is Nonagon a polygon?**

In geometry, a nonagon (/ˈnɒnəɡɒn/) or enneagon (/ˈɛniəɡɒn/) is a nine-sided polygon or 9-gon. The name nonagon is a prefix hybrid formation, from Latin (nonus, “ninth” + gonon), used equivalently, attested already in the 16th century in French nonogone and in English from the 17th century.

## How do you find the exterior angle of a polygon with 12 sides?

For a regular n -gon, the measure of an exterior angle is 360˚n . Since a dodecagon has 12 sides, an exterior angles is 360˚12=30˚ .

## What kind of shape has 12 sides?

dodecagon

A dodecagon is a 12-sided polygon. Several special types of dodecagons are illustrated above. In particular, a dodecagon with vertices equally spaced around a circle and with all sides the same length is a regular polygon known as a regular dodecagon.

**What is a polygon with 13 sides called?**

A 13-sided polygon, sometimes also called the triskaidecagon.