Respostas

2014-04-26T11:48:11-03:00
2x-4 = -x+5
2x+x = 5+4
3x=9
x=9/3
x=3
2014-04-26T11:49:30-03:00
2x - 4 = -x + 5 
2x + x = +4 +5
3x = +9
x = 3