Respostas

A melhor resposta!
2014-04-22T21:26:43-03:00
1)   (2x + 5y – 2) + (3x + y) = 
2x + 5y – 2 + 3x + y = 
5x + 6y – 2

2)   (2x + 5y – 2) – (3x + y) = 
2x + 5y – 2 – 3x – y = 
– x + 4y – 2
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