périmètre

Périmètre is a French word that translates to "perimeter" in English. It refers to the continuous line forming the boundary of a closed geometric figure or area. In simpler terms, it is the total distance around the outside of a shape.

The concept of perimeter is fundamental in geometry and has numerous practical applications. For instance, when fencing a garden, the length of the fence needed corresponds to the perimeter of the garden. Similarly, when measuring the length of a race track, one is measuring its perimeter.

Calculating the perimeter depends on the shape in question. For a rectangle, the perimeter is found by adding the lengths of all four sides. If a rectangle has a length L and a width W, its perimeter P is given by the formula P = 2L + 2W. For a square, which is a special type of rectangle with all sides equal, if the side length is S, the perimeter is P = 4S.

For a circle, the perimeter is called the circumference. The formula for the circumference C of a circle with radius r is C = 2πr, where π (pi) is a mathematical constant approximately equal to 3.14159. For irregular shapes, the perimeter can be found by summing the lengths of all the individual segments that make up the boundary. Understanding perimeter is crucial for area calculations, construction, and various design projects.