Respostas

2014-05-20T21:45:21-03:00
523 - 2x = 387
523 - 387 = 2x
136 = 2x
68 = x
2014-05-20T21:49:27-03:00
523-2x=387
523-387=2x
136/2 = X
X = 136/2 => X= 68