Respostas

2014-06-01T16:06:43-03:00
2× - (7× + 1 - 3×) - (2×y + 7y - 2) + (-5y - 7× + 2×y)
2× - 7× - 1 + 3× - 2×y - 7y + 2 -5y - 7× + 2×y
-9x +1 -12y

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