# What is the formula of a rectangle?

A rectangle is a closed two-dimensional figure in which the opposite sides are equal and all the angles are equal to 90 degrees.

## Answer: The formulas of a rectangle are based on its basic properties which state that it is a quadrilateral in which the opposite sides are equal and parallel and all the interior angles are equal to 90 degrees.

Let us see the formulas of a rectangle in the following section.

**Explanation:**

The following are the main formulas used to calculate the dimensions related to a rectangle:

- The formula for the diagonal of a rectangle is derived using the Pythagoras theorem. Diagonal of Rectangle (d) = √(l² + w²); where 'l' is the length and 'w' is the width of the rectangle.
- The area of a rectangle is the number of unit squares that can fit into it. Area of a Rectangle = (Length × Width)
- The perimeter of a rectangle is the length of its outer boundary. Perimeter of a Rectangle Formula = 2 (Length + Width)