If the area and circumference of a circle are x square cm and x cm respectively,what should be the value of X ?
A)Ï€. C)4Ï€
B)2Ï€. D)Cannot be determined
just set them equal:
πr^2 = 2πr = x
Now eliminate r, and you have
r = x/(2π)
π(x/(2π))^2 = x
πx^2 = 4π^2x
x = 4π
check:
2π*(4π/2π) = 4π
π(4π/2π)^2 = 4π