the area of a circle is found by the equation A=pie r^2, if the area of a certain circle is 64 pie square centimeters, find its radius r.
2007-10-18 10:33:11 · 5 answers · asked by Dill K 1 in Science & Mathematics ➔ Mathematics
radius would be 8cm
A=pi r ^2
64pi=pi r ^2
divide both sides by pi
64=r^2
take the sq root of 64 and you are left with 8
2007-10-18 10:38:41 · answer #1 · answered by cow9634 3 · 0⤊ 0⤋
the area of a circle is found by the equation A=pie r^2, if the area of a certain circle is 64 pie square centimeters, find its radius r.
A =Pi r^2 =64Pi
r^2 =64
r = sqrt (64) = 8 cm
2007-10-18 17:39:14 · answer #2 · answered by Any day 6 · 0⤊ 0⤋
Given:
A=pi*r^2
A=64*pi
Substitute 64*pi for A in the 1st equation
64*pi=pi*r^2
Divide both sides by pi:
64=r^2
Take square root of both sides:
r=8 cm
2007-10-18 17:39:45 · answer #3 · answered by Anonymous · 0⤊ 0⤋
A = 64*pi = pi*r^2
64 = r^2
r = 8 cm
2007-10-18 17:39:06 · answer #4 · answered by Anonymous · 0⤊ 0⤋
64 pi = pi r^2
64 = r^2
r = 8 cm
2007-10-18 17:40:33 · answer #5 · answered by ironduke8159 7 · 0⤊ 0⤋