What is the formula to find the area of a circle if you already know the circumference?

Answer 1

Area = (pi) * (square of the radius) sq. units

Circumference = 2 * (pi) * (radius) units

Just divide circumference by 2 and multiply it with the radius to get area.

Area = (Circumference/2) * (radius)

Answer 2

The formula for area is pi times radius squared where pi is equal to circumference divided by the diameter. So you would need to have the measure of the radius or the diameter to complete the problem. (The radius is equal to one-half the diameter.)

Area = (C/d) x (r^2)

Answer 3

In circles the section is comparable to 3.14 (p) cases the radius (r) to the potential of two. subsequently the formulation sounds like: A= pr2. In circles the circumference is 3.14 (p) cases the Diameter. subsequently the formulation sounds like: 2pr or pd.

Answer 4

Circumfrance = 2*pi*r, where pi = 3.14 and r = radius
Area = pi*r^2

if you know the circumfrance, you can find the radius which then you can find the area. to find the radius, divide the circumfrance by 2*pi, or 6.28.

since you have the radius now, you can square it, and then multiply by pi to find the area.

Answer 5

From the circumference(c), you should calculate the radius(r):

r = c / (2TT)

Substitute this value to find the area as:

Area = TT r^2
Area = TT (c / 2TT)^2

Area = c^2 / 4TT

Answer 6

(C^2)/4π

Since C = 2πr and A = πr^2, we solve C = 2πr for r and then substitute that answer for r in A = πr^2.

C = 2πr
C/2 = πr
(C/2)/π = r
C/2π = r

Now that r has been solved, we substitue that answer for r into A = πr^2.

A = πr^2
A = π(C/2π)^2
A = (πC^2)/(4π^2)
A = (C^2)/4π

Therefore:

A = (C^2)/4π

Answer 7

c = 2 π r
r = c / 2 π
Area = π r²
Area = π.(c²/ 4π²)
Area = c² / 4π