Respostas

2014-05-11T18:24:27-03:00
2x - y ; x = -3 e y = -5
2.(-3) - (-5)
- 6 + 5
- 1

6xy - 5y ; x = -4 e y = -2
6.(-4).(-2) - 5.(-2)
- 48 + 10
- 38
1 1 1