Jawabanmu

2014-03-25T21:33:59+07:00
2.phi.d=7850"3925=phi.d"d=3925÷3, 14=1250"d=1250 cm
2014-03-25T21:34:47+07:00
L = π.r²
7850 = 3,14.r²
r² = 7850/3,14
r² = 2500
r = 50cm

jadi Diameter = 2r =2(50) = 100cm

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