Enter here an algebraic expression that gives the area of a circle with a circumference .
2006-10-01 08:06:26 · 8 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
If C is the circumference then A=C^2/4*pi or Circumference squared divided by 4 pi.
2006-10-01 08:10:19 · answer #1 · answered by jdomanico 4 · 0⤊ 0⤋
The area of a circle is A=pi*r^2, where r is the radius.
The circumference is C=2*pi*r.
It follows that r=C/(2*pi), so if you substitute that into the expression for A, you get
A=pi*(C/(2*pi))^2 = C^2/4*pi.
2006-10-01 08:49:21 · answer #2 · answered by James L 5 · 0⤊ 0⤋
Start with the basics...
Let A = Area (of Circle)
We know that A = pi * r^2
If C = Circumference of a circle...
C = pi * d
or, C = pi * 2r
rewrite this in terms of r...
r = C/(2*pi)
substitute into the original equation for area, A = pi * r^2, and you get...
A = pi * (c/(2*pi))^2
which reduces to...
A = pi * (c^2 / (4*pi^2)
which reduces to...
A = 1/4 * C^2 / pi
2006-10-01 08:20:28 · answer #3 · answered by 2Horses 2 · 0⤊ 0⤋
circumference of a circle with radius C = 2 * pi * r
area of a circle with radius A = pi r^2
Therefore, if you know the circumference C, r = C / (2 * pi)
and substituting the radius in terms of the circumference in for the radius in the area formaula,
A = pi * (C/2*pi)^2 = pi * (C^2)/(2^2 * pi^2) = (1/4 pi^2) * C
A = C /(4 * pi^2)
Is that what you mean?
2006-10-01 08:12:15 · answer #4 · answered by spongeworthy_us 6 · 1⤊ 0⤋
The area of a circle is 360 degrees
2006-10-01 08:50:50 · answer #5 · answered by cuty 1 · 0⤊ 0⤋
A of circle = pi r squared
circumference = 2r pi (or d pi)
figure it out
2006-10-01 08:10:26 · answer #6 · answered by Vanna 2 · 0⤊ 0⤋
C = 2*pi*r
So, r = C/(2pi)
A = pi*r^2
So, A = pi*(C/2pi)^2
Simplifies to
A = C^2/4pi
2006-10-01 08:23:19 · answer #7 · answered by whatthe 3 · 0⤊ 0⤋
F(x) (-x *z) + c +9 /y = F(x) (3.14)(r)(r) (-x *z) +9 /y
2006-10-01 08:09:29 · answer #8 · answered by Teacher Man 6 · 0⤊ 0⤋