Using 3.14 as Pi the area of circle is: 28.259999999999998
The radius is half the diameter.
The radius is a lenght, and it's impossible to find out the radius if you don't give any information about the size of your circle.
Will give the circumference of half of the circle.
Circumference is calculated from radius as C = pi x r x 2 To find the circumference of a circle with a diameter of 8 meters, simply multiply the radius (8) by 2, then multiply the product by pi (approximately 3.14159). This should give you around 50.3 meters.
By dividing the diameter by 2 will give the circle's radius. Area of any circle = pi*radius squared.
Measure the diametre of the circle and divide by two to give the radius.
Divide its circumference by 2*pi which will give the radius of the circle. Area of the circle then is pi*radius squared
Doubling the radius will give the diameter and times this by pi will give the circumference of the circle.
Divide the circumference by 2*pi will give the radius of the circle.
the equation for the circumference of a circle is 2*radius*pi, or since the radius is half of the diameter 2*radius=diameter, we can simplify the equation to the circumference of a circle=diameter*pi
area of a circle = pi * radius² = 1 radius = √(1/pi) circumference = 2pi * radius = 2pi * √(1/pi) = 3.5449077
Divide the area by pi and then square root it this will give the radius of the circle.