Jawabanmu

2014-01-30T07:28:58+07:00
2014-01-30T07:35:43+07:00
F1 = 4 N resultan = 5N
resultan = Fa- Fb
          5N = Fa - 4N
             Fa = 5N+4N
               F2 = 9N
7 4 7