Respostas

2014-08-30T14:21:43-03:00
3a+3a = 6a
2b+5b= 7b
7
2014-08-30T14:22:09-03:00
3a + 2b + 3a + 5b + 7=
3a + 3a + 2b +5b +7=
6a +7b + 7