Resposta :
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7y - 12 = 5y + 8
7y - 12 - 5y = 8
2y - 12 = 8
2y = 8 + 12
2y = 20
y = 20/2
y = 10
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Att: MarcosPCV
7y - 12 = 5y + 8
7y - 12 - 5y = 8
2y - 12 = 8
2y = 8 + 12
2y = 20
y = 20/2
y = 10
Att: MarcosPCV