How to Calculate the Area of a Circle

What is the formula to calculate the area of a circle?

Given the radius of a circle is 5 cm, what is the area of the circle?

Formula to Calculate Area of a Circle

The formula to calculate the area of a circle is πr2, where π (pi) is approximately 3.14159 and r is the radius of the circle.

Calculation

Given the radius, r = 5 cm

Area = π(5)2

Area = 3.14159(25)

Area = 78.54 cm2

To calculate the area of a circle, you need to use the formula πr2, where π (pi) is a constant approximately equal to 3.14159 and r is the radius of the circle. In the given example, with a radius of 5 cm, you can substitute the radius value into the formula and calculate the area. Simply square the radius and multiply it by π to find the area.

For a circle with a radius of 5 cm, the area would be 78.54 cm2. Remember to always include the unit squared (cm2) when expressing the area of a circle to indicate the measurement is for area.

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