tentukan diameter lingkaran yang mempunyai luas 314 cm

L lingkaran = phi × r^2
314 = 3,14 × r^2
r^2 = 314 / 3,14
r^2 = 100
r = akar 100
r = 10
diameter = 2 × r = 2 × 10 = 20 cm

L =314cm^2

L = phix r^2
314 cm^2 = 3,14 r^2
r^2 = 314/3,14
r^2= 100
r = akar 100
r = 10

d =2xr
d= 2x 10
d=20