Respostas

2014-05-24T11:38:10-03:00
3a + b = 4
a - b = 2

4a = 6 ----> a = 6/4 ----> a = 3/2
a - b = 2 ----> 3/2 - b = 2
b = -1/2

Resposta: a= 3/2 b= -1/2