To recall, the area is the an ar that populated the form in a two-dimensional plane. In this article, friend will find out the area of a circle and the formulas for calculating the area of a circle.

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What is the Area that a Circle?

The area that the one is the measure up of the room or an ar enclosed inside the circle. In an easy words, the area of a one is the total number of square units inside that circle.

For example, if you draw squares of dimensions 1cm by 1cm inside a circle. Then, the total number of full squares situated inside the circle represents the area that the circle. We deserve to measure the area of a circle in m2, km2, in2, mm2, etc.

Formula because that the Area of a Circle

The area the a circle deserve to be calculated using three formulas. This formulas are used depending ~ above the details you space given.

Let us talk about these formulas because that finding the area of a circle.

Area of a circle utilizing the radius

Given the radius that a circle, the formula because that calculating the area of a circle states that:

Area of a circle = πr2 square units

A = πr2 square units

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Solution

Given the diameter,

A = πd2/4 square units

= 3.14 x 502/4

= (3.14 x 50 x 50)/4

=1962.5 cm2

Example 7

Calculate the area of a dinner plate, which has actually a diameter the 10 cm.

Solution

A = πd2/4 square units

= 3.14 x 102/4

= (3.14 x 10 x 10)/4

= 78.5 cm2

Example 8

The diameter of a circular key is 20 cm. Uncover the size of a square plate that will have actually the same area as the one plate.

Solution

Equate the area the the circle come the area the the square

πd2/4 = s2

3.14 x 202/4 = s2

s2 =314

Find the square source of both sides to get,

s = 17.72

Therefore, the size of the square plate will certainly be 17.72 centimeter by 17.72 cm.

Example 9

Find the diameter that a circle through an area the 156 m2.

Solution

A = πd2/4

156 = 3.14d2/4

Multiply both sides by 4.

624 = 3.14d2

Divide both sides by 3.14.

198.726 = d2

d = 14.1 m

Thus, the diameter that the circle will certainly be 14.1 m.

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Area of a circle making use of the circumference

As we currently know, the circumference of a circle is the distance around a circle. It is possible to calculate the area that a circle offered its circumference.