Răspuns:
Explicație pas cu pas:
L=2πR=Dπ D=L:π D=2R
a)D=44:3,14≅14,01 cm
b)D=12:3,14≅3,82m
c)D=70:3,14≅22,29 cm
L=2πR A=πR² R=√A:π=
a) R=√64/√π=≅√20,38=4,51 cm
L=2π×4,51=28,35 cm
b) R=11√π/π
L=2π×11√π/π=22√3,14=38,98 cm
c)R=2√5π/π
L=2π×2√5π/π=4√5π==15,85 cm