Respostas

2013-09-04T14:35:24-03:00
Y-4y = -6 + 3y
-3y = -6 +3y
-3y -3y = -6
-6y = -6
6y=6
y = 6/6 = 1
2013-09-04T14:35:40-03:00
Y-4y=6+3y
3y=6+3y
3y-3y=6
cacelando os dois vai sobrar 6