Please show all work.
Thank you very much :)
2007-08-13 14:05:18 · 5 answers · asked by Elizabeth 3 in Science & Mathematics ➔ Mathematics
A = π*r^2
C = 2*π*r
C^2 = 4*π^2*r^2
C^2 = 4*π*(π*r^2)
C^2 / (4*π) = π*r^2
A = C^2 / (4*π)
2007-08-13 14:11:21 · answer #1 · answered by lithiumdeuteride 7 · 0⤊ 1⤋
A=pi(r)^2 area of the circle
C=2pir- circumference of the circle
c^2=4pi^2 r^2.
A/C^2=1/4pi
A=C^2/4pi ANS
2007-08-13 21:14:49 · answer #2 · answered by Anonymous · 0⤊ 1⤋
C = 2pi r
so r = C/(2pi)
A = pi r^2
so A = pi (C/(2pi))^2 = pi C^2/(4 pi^2) = C^2/(4 pi)
2007-08-13 21:11:43 · answer #3 · answered by hemidemisemiquaver 2 · 0⤊ 1⤋
A=pi.r^2
C=2.pi.r=>r=C/(2.pi)
plug it in the area formula
A=pi.C^2/(4.pi^2)=C^2/(4.pi)
2007-08-13 21:14:07 · answer #4 · answered by Alberd 4 · 0⤊ 1⤋
C = 2 * Pi * r
r = C/2*Pi
A = Pi* r^2
r = (A/Pi)^0.5
(A/Pi)^0.5 = C/2*Pi
A/Pi = (C/2*Pi)^2
A = C^2/4*Pi^2 * Pi
A = C^2/4*Pi
2007-08-13 21:14:49 · answer #5 · answered by gebobs 6 · 0⤊ 0⤋