Rectangle

A rectangle

In geometry, a rectangle is a shape with four sides and four corners. The corners are all right angles. It follows that the pairs of sides opposite each other must be parallel and of the same length.

People make many rectangular things, including most tables, boxes, books, and papers. The word comes from Latin words meaning "right" and angle".

A rectangle whose four sides have the same length is called a square.

Formulas

The formula for the perimeter of a rectangle.

If a rectangle has length [math]\displaystyle{ \ell }[/math] and width w, then:

• It has area [math]\displaystyle{ K = \ell w }[/math].
• it has perimeter [math]\displaystyle{ P = 2\ell + 2w = 2(\ell + w)\, }[/math].
• Each diagonal has length [math]\displaystyle{ d=\sqrt{\ell^2 + w^2} }[/math].
• it has an aspect ratio of [math]\displaystyle{ \ell }[/math] : w.
• When [math]\displaystyle{ \ell = w\, }[/math], the rectangle is a square.
• When [math]\displaystyle{ \ell / w }[/math] is equal to the golden ratio, the rectangle is called a golden rectangle.

Rectangle Media

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  A rectangle is a special case of both parallelogram and trapezoid. A square is a special case of a rectangle.

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  The area of a rectangle is the product of the length and width.

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  Crossed-rectangle

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  A saddle rectangle has 4 nonplanar vertices, alternated from vertices of a rectangular cuboid, with a unique minimal surface interior defined as a linear combination of the four vertices, creating a saddle surface. This example shows 4 blue edges of the rectangle, and two green diagonals, all being diagonal of the cuboid rectangular faces.

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  brickwork stacked bond

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  Wallpapergroupcmm

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  Wallpapergrouppg

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  A basketweave bond in bricklaying.

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  A herringbone bond in bricklaying.

Related pages

• Matrix (mathematics)
• Quadrilateral
• Rhombus