Jawabanmu

2014-02-27T18:31:11+07:00
25-4y=6y+15 -10y= -10 y= 1
25-15=6y+4y => 10=10y => y= 10/10 => y=1
2014-02-27T18:38:00+07:00
25-4y =6y+15
-4y-6y =15-25
-10y    =-10
          y=1