Respostas

2013-09-03T21:28:07-03:00
(3x-6)-(1-x)=13
3x-6-1+x=13
4x = 13+7
x = 20/4
x = 5
2013-09-03T23:47:18-03:00
3x - 6 -1 - x = 13
2x = -6 -1 - 13
2x = -20
x = -20 / 2 =
x = -10