Geometric figures

The perimeter in a geometric figure: concept, definition and examples

The perimeter in a geometric figure: concept, definition and examples

One of the most basic and essential concepts in geometry is the perimeter. The perimeter of a geometric figure is a measurement that provides us with information about the total length of its contour.

The term "perimeter" comes from the Greek "peri" (around) and "metron" (measure), which gives us a clue as to its meaning.

In geometry, the perimeter refers to the sum of the lengths of all the sides that make up a figure. In other words, it is the measurement of the distance around the edge of a geometric figure.

Perimeter is generally expressed in units of length, such as centimeters, meters, feet, or inches, depending on the measurement system used.

Calculation of perimeter in basic figures

The calculation of the perimeter varies depending on the type of geometric figure. Here, let's examine how it is calculated on some basic geometric figures:

1. Perimeter in a square

A square is a geometric figure with four equal sides. To calculate its perimeter, it is enough to multiply the length of one of the sides by 4. If we denote the side of the square as "l", the perimeter (P) is calculated as follows:


2. Perimeter in a rectangle

A rectangle is a figure with two pairs of equal sides and right angles. To calculate its perimeter, we add twice the length of one side (long side) and twice the length of the other side (short side). If we call the long side "L" and the short side "l", the perimeter (P) is calculated like this:


3. Perimeter in a triangle

A triangle has three sides. The calculation of the perimeter depends on whether the triangle is equilateral, isosceles or scalene. In an equilateral triangle, where all sides are equal, the perimeter (P) is calculated by multiplying the length of one side by 3. In an isosceles or scalene triangle, the length of the three sides is added to obtain the perimeter.

4. Perimeter in a circle

The circle is a special figure since it does not have straight sides. Instead of measuring the sides, we measure the distance around the edge of the circle, which is called the circumference. The formula to calculate the circumference (C) of a circle is:


Where "r" is the radius of the circle and "π" is a constant approximately equal to 3.14159.

Importance of perimeter

The perimeter in a geometric figure: concept, definition and examplesThe calculation of perimeter is fundamental in geometry and has many applications in everyday life. Some of the reasons why perimeter is important include:

  • In construction and architecture, calculating perimeter is essential for determining the amount of material needed for fences, walls, wiring, and more.

  • In garden and landscaping design, perimeter calculation is vital in determining the amount of grass, fences or shrubs needed for a given area.

  • Mathematical Problem Solving: Calculating perimeter is an essential mathematical skill used to solve a wide variety of problems in geometry.

  • In the world of logistics and transportation, perimeter calculation is relevant to determining how many products can fit in a given area, such as in a cargo truck or shipping container.

  • Artists often use the concept of perimeter to design balanced and aesthetically pleasing visual compositions.


In summary, perimeter is a fundamental measurement in geometry that provides information about the total length of the contour of a geometric figure.

The calculation of perimeter varies depending on the type of figure, but its usefulness extends to a wide range of applications in everyday life, from construction to art. By understanding and applying the concept of perimeter, we can solve mathematical problems, make decisions in everyday life, and better appreciate the world around us.

Publication Date: October 10, 2023
Last Revision: October 11, 2023