Jawabanmu

2013-12-08T23:11:25+07:00
Θ=90o > (90o) (2πrad/360o) = 2π/4.rad

jari2= 5cm

x=Rθ
x=(5cm) (2π/4.rad)
x=10/4 π cm
x=10/4 3,14 cm
x= 7,85 cm