Rectangle

In this publication, we will consider the definition, properties and characteristics of one of the main geometric shapes - a rectangle. We also present formulas with which you can find its area and perimeter.

A rectangle is a quadrilateral in which all angles are 90° (i.e., are straight).

Formulas:

1. Area of the rectangle (S):

S = a ⋅ b

See online calculator - Rectangle Area Calculator.

2. Perimeter of the rectangle (P):

P = a + a + b + b = 2a + 2b

See online calculator - Rectangle Perimeter Calculator.

The rectangle consists of:

lengths are a longer pair of sides. Usually indicated by a Latin letter, for example, a;
widths are a shorter pair of sides. Most often referred to as b.
The rectangle itself is usually written by listing its vertices, for example, ABCD in our case.

Note: The rectangle is a kind of parallelogram.

The opposite sides of the rectangle are parallel and equal in pairs.

The length and width of the rectangle are simultaneously its heights, since they are mutually perpendicular.

If you connect the midpoints of the sides of the rectangle, you get a rhombus.

The square of the diagonal (d) of a rectangle is the sum of the squares of its adjacent sides.

The diagonals of the rectangle are equal and are halved at the intersection.

Around any rectangle, you can describe a circle whose radius (R) is equal to half the diagonal of this rectangle.