To recall, the area is the an ar that lived in the form in a two-dimensional plane. In this article, girlfriend will discover the area the a circle and the formulas because that calculating the area that a circle.

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What is the Area that a Circle?

The area of the one is the measure of the room or region enclosed inside the circle. In an easy words, the area of a circle is the total variety of square devices inside the circle.

For example, if you draw squares of size 1cm by 1cm inside a circle. Then, the total variety of full squares located inside the circle represents the area the the circle. We have the right to measure the area the a one in m2, km2, in2, mm2, etc.

Formula for the Area of a Circle

The area that a circle have the right to be calculated using 3 formulas. This formulas are applied depending top top the info you are given.

Let us comment on these formulas because that finding the area the a circle.

Area the a circle utilizing the radius

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

Area the a one = 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 the 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 plate is 20 cm. Discover the dimensions of a square plate the will have the very same area as the one plate.

Solution

Equate the area of the circle to the area that the square

πd2/4 = s2

3.14 x 202/4 = s2

s2 =314

Find the square root of both political parties to get,

s = 17.72

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

Example 9

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

Solution

A = πd2/4

156 = 3.14d2/4

Multiply both political parties 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 that a circle using the circumference

As we already know, the circumference of a circle is the distance approximately a circle. The is feasible to calculation the area that a circle offered its circumference.