The Lesson

A rectangle is a four sided shape with four right angles.

a rectangle

Dictionary Definition

The Oxford English Dictionary defines a rectangle as "a plane figure with four straight sides and four right angles, opposite sides being parallel and equal in length; especially one in which adjacent sides are unequal, as contrasted with a square."

Properties of Rectangles

  • Opposite sides of a rectangle are of equal length.

    opposite sides of a rectangle are equal
  • All angles in a rectangle are right angles.

    all angles in a rectangle are right angles
  • Opposite sides of a rectangle are parallel.

    opposite sides of a rectangle are parallel
  • All angles of a rectangle add up to 360°.

    all angles in a rectangle add up to 360 degrees
  • The diagonals of a rectangle are equal in length. They bisect each other. They cross each other half-way along their lengths.

    diagonals of a rectangle bisect each other

The Perimeter of a Rectangle

The perimeter of a rectangle is given by the formula:

perimeter of a rectangle equals 2 (b plus h) In this formula, b is the length of the base and h is the height of the rectangle.

The Area of a Rectangle

The area of a rectangle is given by the formula:

area of a rectangle equals b h In this formula, b is the length of the base and h is the height of the rectangle.
Read more about how to find the area of a rectangle

Interactive Widget

Here is an interactive widget to help you learn about rectangles.

A Rectangle is a Polygon

A rectangle is a type of polygon. A polygon is a 2-dimensional shape with straight sides. A rectangle is an irregular polygon. It has different length sides.

A Rectangle Is a Quadrilateral

A rectangle is a quadrilateral. A rectangle is a four-sided polygon. Parallelograms, squares and trapezoids are also quadrilaterals.