Definition of

# Rectangle

The Latin word *rectanglelus* came to our language **rectangle**. As a noun, the term is used to name the **polygon** It has four sides (two of one length and two of a different length) that form four 90º angles.

To understand what a rectangle is, we can start from the most elementary concept until we reach the notion in question. First, a rectangle is a **polygon**: a plane figure that is formed by **segments** -known as **sides**– that come together, giving rise to a closed figure.

**what is a rectangle****Your ranking****The rectangle in road safety****A type of right angle**- Related Topics Tree

## what is a rectangle

Within the broad group of polygons, the rectangle is a **quadrilateral** since it has four sides. If we analyze the quadrilaterals, on the other hand, the rectangle is qualified as **parallelogram**since its sides are two-way parallel (two sides are parallel to each other, while the other two are also parallel to each other).

Finally, already focused on the specific group of **parallelograms**we can say that a rectangle is one whose opposite sides measure the same and the four sides create right angles (of 90º).

The rectangles, in short, are **polygons, quadrilaterals and parallelograms**. to know your **surface**, it is necessary to multiply two of the adjacent sides. If the intention is to calculate the **perimeter**it is enough to add the four sides.

It can help you: Regular polygon

## Your ranking

In addition to all of the above, it is important that we know that, as a general rule, rectangles are usually classified into three large groups:

-The **irrational**. This set is made up of a great variety of rectangles such as the golden one, whose sides have the unit and the number of gold; the Cordoba, so called because it was a very unique one used by the architects who built the famous Mosque of Cordoba; the rectangle n, which has the unit and the number n…

-The **static**, which are those that are made up of sides that have integer dimensions. Within this typology we could highlight, for the best known being, the one that responds to the name of Egyptian.

-The **dynamic**. In this case, we have to state that they are the ones obtained from what is the diagonal of a previous rectangle. This will make it keep one of its sides and the length of the other side will be that of the diagonal belonging to the starting rectangle.

See also: Singular

## The rectangle in road safety

Within the field of road safety in general, the rectangle is very important because there are many signs that take this shape. Specifically, we are referring to what are known as informative traffic signs which, in addition to this aforementioned characteristic, have a blue frame, a white base and their symbol is black.

Examples of this type of signs are those that indicate a bus stop, a nearby hospital, the airport, a pedestrian crossing, a taxi rank, the existence of a viewpoint, a tourist information point…

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## A type of right angle

As **adjective**, on the other hand, rectangle is the qualification given to a triangle that has a right angle. In this case, one speaks of **right triangles**.

If the triangle has an angle greater than 90º, it will be qualified as **obtuse angle**while if all its angles measure less than 90º, it will be defined as a triangle **acute angled**.

See also: Equilateral triangle