Respostas

2014-03-28T15:03:39-03:00
23X+X=15-87        24X=-72      X=-72 / 24 = -3
2014-03-28T15:16:36-03:00
23x+87=-x+15
24x= 15-87
24x= -72
x= 24/-72
x= -3