Respostas

2014-06-03T22:32:00-03:00
5x-18=2x+3
5x-2x=18+3
3x=21
x=21/3
x=7
2014-06-03T22:38:09-03:00
5x-18=2x+3
5x-2x=3+18
3x=21
x=21
    3
x=7