Area of a circle
Area of a Circle
Definition of Area
The area of a circle is defined as the amount of space contained within the boundary of the circle.
Formula for Area of a Circle
The area can be calculated using the formula:
ext{Area} = ext{pi} imes ext{radius}^2This formula can also be represented in a more concise form as:
A = ext{pi} imes r^2
where:A = Area
r = Radius
pi (π) is a mathematical constant approximately equal to 3.14.
Units of Area
The resulting area will be in squared units (e.g., square centimeters, square meters).
Example Calculation
If the radius of the circle is given as 5 centimeters, we can calculate the area as follows:
Substitute the radius into the formula:
ext{Area} = ext{pi} imes (5 ext{ cm})^2Calculate the radius squared:
5^2 = 25 ext{ cm}^2Multiply by pi:
ext{Area} = 3.14 imes 25 ext{ cm}^2Perform the multiplication:
ext{Area} = 78.5 ext{ cm}^2
Final Result
Therefore, the area of the circle with a radius of 5 centimeters is:
ext{Area} = 78.5 ext{ cm}^2