Jawabanmu

2014-01-19T14:41:17+07:00
1.  -5b - 4b + 10 = 1
     -5b - 4b = 1 - 10
      -9b = -9
      b = -9 / -9
      b = 1

2.  2 + a / 4 = 5
     2 + a = 5 x 4
     2 + a = 20
     a = 20 - 2
     a = 18