# Rectangle Is A

The area of a rectangle is the space contained within its perimeter. The grey space is the area of the rectangle in the diagram below.

Use this calculator if you know 2 values for the rectangle, including 1 side length, along with area, perimeter or diagonals and you can calculate the other 3 rectangle variables. A square calculator is a special case of the rectangle where the lengths of a and b are equal.

## Area formula of a rectangle

- Golden Rectangle. Definition: A golden rectangle is a rectangle that can be cut up into a square and a rectangle similar to the original one. More precisely, Let ABCD.
- Rectangle definition, a parallelogram having four right angles.

The area, A, of a rectangle is the product of its length, l, and width, w.

A = l×w

*Note: Sometimes, base and height are used instead of length and width.*Deinterlace footage adobe media encoder cc.

### Area formula using the diagonal

If the diagonal, d, and one side, s, of the rectangle are known, the following area formula can be used:

Example:

Find the area of the rectangle below that has a diagonal of 26 and length of 24.

Since the area of a rectangle is a product of its length and width, we need to find the width. The diagonal of a rectangle divides it into two congruent right triangles. Using the Pythagorean theorem:

w^{2} + 24^{2} = 26^{2}

w^{2} + 576 = 676

w^{2} = 100

w = 10

The area of the rectangle is:

A = l×w = 24×10 = 240

Using the diagonal and side length formula:

A = | |

= | |

= | 24 × 10 |

= | 240 |

## Finding area using a grid

Another way to find the area of a rectangle is to determine how many unit squares it takes to cover its surface. Below is a unit square with length 1 cm.

A grid of unit squares can be used when determining the area of a rectangle.

The grid above contains unit squares that have an area of 1 cm^{2} each. The rectangle on the left contains 8-unit squares, so it has an area of 8 cm^{2}. The rectangle to the right contains 20-unit squares, so it has an area of 20 cm^{2}.

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## Rectangle Shape

a = length side a

b = length side b

p = q = diagonals

P = perimeter

A = area

√ = square root

## Calculator Use

Use this calculator if you know 2 values for the rectangle, including 1 side length, along with area, perimeter or diagonals and you can calculate the other 3 rectangle variables. A square calculator is a special case of the rectangle where the lengths of a and b are equal.

**Units:** Note that units of length are shown for convenience. They do not affect the calculations. The units are in place to give an indication of the order of the calculated results such as ft, ft^{2} or ft^{3}. Any other base unit can be substituted.

## Rectangle Formulas

### Area of a rectangle:

A = ab

## Is A Rectangle A Polygon

### Perimeter of a rectangle:

## Rectangle Is A Trapezoid

P = 2a + 2b

### Polygon diagonals of a rectangle:

p = q = √(a^{2} + b^{2})

## Rectangle Calculations

**Calculate A, P, p Given a, b**

Given sides lengths a and b calculate area, perimeter and diagonals- A = ab
- P = 2a + 2b
- p = q = √(a
^{2}+ b^{2})

**Calculate P, p, b Given A, a**

Given area and side length a calculate perimeter, diagonals and side b- b = A / a
- P = 2a + 2b
- p = q = √(a
^{2}+ b^{2})

**Calculate P, p, a Given A, b**

Given area and side length b calculate perimeter, diagonals and side a- a = A / b
- P = 2a + 2b
- p = q = √(a
^{2}+ b^{2})

**Calculate A, p, b Given P, a**

Given perimeter and side length a calculate area, diagonals and side b- b = (P - 2a) / 2
- A = ab
- p = q = √(a
^{2}+ b^{2})

**Calculate A, p, a Given P, b**

Given perimeter and side length b calculate area, diagonals and side a- a = (P - 2b) / 2
- A = ab
- p = q = √(a
^{2}+ b^{2})

**Calculate A, P, b Given p, a**

Given diagonals and side length a calculate area, perimeter and side b- b = √(p
^{2}- a^{2}) - A = ab
- P = 2a + 2b

- b = √(p
**Calculate A, P, a Given p, b**

Given diagonals and side length b calculate area, perimeter and side a- a = √(p
^{2}- b^{2}) - A = ab
- P = 2a + 2b

- a = √(p

**Cite this content, page or calculator as:**

## Rectangle Is A Quadrilateral

Furey, Edward 'Rectangle Calculator'; CalculatorSoup, *https://www.calculatorsoup.com* - Online Calculators