Respostas

2013-09-09T22:01:12-03:00
2x-4 = 0
2x = 4
x= 4/2
x=2
some x+x = 2x e 7-10-1 = -4 , logo 2x-4
2013-09-09T22:06:01-03:00
2x-4
x= -2
N sei c está certo......