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Regular polygon area calculator

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What is a regular polygon area calculator?

A regular polygon area calculator is a valuable tool that helps users quickly compute the area of a regular polygon. A regular polygon is a geometric figure in which all sides and angles are equal. Such polygons have countless applications in various fields, including architecture, engineering, art, and mathematics.

The area of a regular polygon is of interest to many people because of its practical significance. For example, if you are an architect or designer, knowing the area of your designed space can aid in resource planning and allocation. Similarly, if you are a student studying mathematics, this calculator can save you from performing complex calculations manually.

This calculator allows you to specify any number of sides for a regular polygon and automatically calculate the area based on the entered data. This makes it a versatile tool for working with polygons of different shapes and sizes.

Properties of regular polygons

A regular polygon has several unique properties that make its study interesting and useful. Here are a few:

  1. Equality of sides and angles: This is one of the primary properties. Since all sides and angles of a regular polygon are equal, it simplifies the calculation of its area and perimeter.

  2. Central angles: In a regular polygon, the sum of all central angles is 360 degrees. For an n-gon, the measure of each central angle is 360n\frac{360^\circ}{n}.

  3. Circumscribed circles: Regular polygons can always be inscribed and circumscribed about a circle. This means they are symmetric about their center.

Applications of regular polygons

Regular polygons are used in many fields. Let’s consider two main areas:

Architectural design

In architecture, regular polygons are often used because of their symmetry and aesthetic appeal. Beautiful and symmetrical shapes provide not only aesthetic perception but also functional advantages. For example, repeating one shape in structural elements can simplify production and assembly processes.

Art and decoration

In decorative arts and interior design, regular polygons become a source of inspiration. Artists and interior designers often use polygonal motifs to create unique patterns and structures that adorn spaces and objects.

Area formula

The formula for calculating the area of a regular polygon with nn sides and side length ss is expressed as:

A=ns24tan(180n)A = \frac{n \cdot s^2}{4 \cdot \tan{\left(\frac{180}{n}\right)}}

Where:

  • AA denotes the area of the polygon,
  • nn is the number of sides,
  • ss is the length of each side.

This formula is useful because it allows for quick computation of a polygon’s area knowing only the number of its sides and the length of one of them.

Calculation examples

  1. Hexagon: For a regular hexagon with a side of 4 cm:

    • n=6n = 6,
    • s=4s = 4.

    Substitute the values into the formula:

    A=6424tan(1806)=9640.577=41.57cm2A = \frac{6 \cdot 4^2}{4 \cdot \tan{\left(\frac{180}{6}\right)}} = \frac{96}{4 \cdot 0.577} = 41.57 \, \text{cm}^2

  2. Octagon: For a regular octagon with a side of 3 m:

    • n=8n = 8,
    • s=3s = 3.

    Substitute the values into the formula:

    A=8324tan(1808)=7240.414=43.46m2A = \frac{8 \cdot 3^2}{4 \cdot \tan{\left(\frac{180}{8}\right)}} = \frac{72}{4 \cdot 0.414} = 43.46 \, \text{m}^2

Area unit conversion

Sometimes when working with area, you may need to convert units of measurement. Common conversions include:

  • 1m2=10000cm21 \, \text{m}^2 = 10000 \, \text{cm}^2
  • 1km2=1000000m21 \, \text{km}^2 = 1000000 \, \text{m}^2
  • 1are=100m21 \, \text{are} = 100 \, \text{m}^2
  • 1hectare=10000m21 \, \text{hectare} = 10000 \, \text{m}^2

Conversion examples

If the area of a hexagon is 41.57cm241.57 \, \text{cm}^2, converting to square meters is done as follows:

  • 41.57cm2=41.57×0.0001m2=0.004157m241.57 \, \text{cm}^2 = 41.57 \times 0.0001 \, \text{m}^2 = 0.004157 \, \text{m}^2

If the area of an octagon is 43.46m243.46 \, \text{m}^2, converting to hectares is done as follows:

  • 43.46m2=43.46×0.0001ha=0.004346ha43.46 \, \text{m}^2 = 43.46 \times 0.0001 \, \text{ha} = 0.004346 \, \text{ha}

Notes

  1. Always remember to use consistent units of measurement for the side length to correctly apply the formula.

  2. An online calculator can be especially useful for rapid calculations when you need to work with multiple polygons or perform repeated calculations.

  3. Understanding the formula helps users comprehend the geometric principles underlying the structure of polygons.

FAQs

Why are regular polygons preferred in design and architecture?

They are symmetric and aesthetically pleasing, allowing for even distribution of load and materials, which simplifies design processes.

What makes a regular polygon unique?

Its angles and sides are equal, creating a symmetric figure easily inscribed and circumscribed by circles, maintaining proportionality.

What are the characteristics of circumscribed circles?

The circle circumscribing a regular polygon touches all its vertices, creating equal line segments from the center of the circle to each vertex.

How accurate are the results of online regular polygon area calculators?

They typically provide accurate results when input data is correct. However, it’s always wise to verify results with manual calculations to prevent errors.

Can this formula be used for any polygon?

No, the formula is applicable only to regular polygons where all sides and angles are equal.

How to find the area of a regular pentagon with a side of 7 m?

To calculate the area of a regular pentagon, we use the formula outlined above. First, identify the given values:

  • n=5n = 5 (number of sides),
  • s=7s = 7 (length of the side).

Now substitute the values into the formula:

A=5724tan(1805)A = \frac{5 \cdot 7^2}{4 \cdot \tan{\left(\frac{180}{5}\right)}}

Calculate:

  • Square of the side length: 72=497^2 = 49.
  • Value of the tangent: tan(1805)=tan(36)=0.7265 \tan{\left(\frac{180}{5}\right)} = \tan(36^\circ) = 0.7265.

Now compute the area:

A=54940.7265=2452.90684.34m2A = \frac{5 \cdot 49}{4 \cdot 0.7265} = \frac{245}{2.906} \approx 84.34 \, \text{m}^2

The area of a regular pentagon with a side of 7 meters is approximately 84.34m284.34 \, \text{m}^2.