Jawabanmu

2014-01-21T19:01:05+07:00
A. PB =  \frac{ x^{o} }{360}.Keliling O
    PB =  \frac{30}{360}.2. 3,14. 20
    PB = 10.4 Cm

b. LJ =  \frac{ x^{o} }{360}.Luas O
    LJ =  \frac{45}{360}.3,14. 20^{2}
    LJ = 157 Cm

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