Jawabanmu

2014-02-20T18:45:21+07:00
A) 6x +5 = 26 - x
   6x + x = 26 - 5
   7x = 21
    x = 21 : 7
    x = 3

b) x - 12 = 2x + 36
    -12 - 36 = 2x - x
      -48 = x
        x = -48

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