Commit to memory
A = pi r^2
C = 2 pi r or pi d
NB 2r = d
This is elementary school maths.
Hence if d = 2r 8 , then r = 8/2 = 4
Hence
A = pi 4^2
A = 16 pi
pi is a constant at 3.141592....
A = 16*3.41592.... = 50.26554.... units^2
Area is 4.6 m2
in place of r (radius) write d/2 where d is diameter
The radius(radii is the plural) of the circle is half the distance of circle's diameter. The formula is r=(1/2)diameter.
Take the circumference of a circle and divide it by the diameter of that circle: ∏=C/D
divide by pi which is 3.1415927 and on and on
The area of a circle with a diameter of 8 centimeters is: 50.27 square centimeters.
The area of a circle with a diameter of 8 feet is: 50.27 square feet.
A circle with a diameter has an area of 50.265486543928724876568901 sq. ft.
The diameter is 8. The circumference is 8 pi. The area is 16 pi.
The area of a circle with an 8 inch diameter is approximately 50.27 square inches.
50.24
50.3 square feet for an 8-foot diameter circle.
64 pi
The area is 50.3 square feet.
The area is 50.265 square miles.
The area would be 50.3 m2.
The radius is about 8 so the diameter = 2*8 = 16 units in length