# A polygon that has all sides the same measure and all angles the same measure is called what?

Basically, a polygon is a 2-d closed figure, that is made up of three or more straight lines. Some examples of polygons are triangles, squares, pentagons, hexagons, etc.

## Answer: A regular polygon.

**Explanation:**

According to Euclidean Geometry, a polygon that has all angles of the same measure and all sides of the same length is known as a regular polygon.

A regular polygon must have the following properties :

- All its sides should be equal
- All its interior angles should be equal
- All its exterior angles should be equal

Let us apply the three properties of a regular polygon and understand this with the example.

We will check whether the equilateral triangle will fulfill all the above three properties of a regular polygon or not.

We observe that:

The above triangle has all sides equal: AB = BC = CA.

All interior angles measure 60º angles.

All exterior angles measure 120º angles.

Hence, the above triangle ABC is a regular polygon.