Jawabanmu

2014-04-02T21:20:42+07:00
3 = x / 10 - x
30 - 3x = x
30 = 4x
7,5 = x
2014-04-02T21:20:56+07:00
12/4 = x/10 - x
3 = x/10 - x
3 = -9x/10
-9x = 30
x = -10/3
  = -3,333333...