Jawabanmu

2014-02-18T16:48:20+07:00
Bilok Na = +1 dan Bilok O = -2 sehingga

 2(1) + 2S + 3(-2)  = 0
2 + 2S  -6 = 0
2S -4 = 0
S  = 4/2 = 2

2014-02-18T17:34:08+07:00
2 (1) + 2S + 3(-2)
= 2 + 2S - 6
2S = 6 - 2
S = 4/2
S = 2