Respostas

2013-08-06T17:48:05-03:00
2(x-5)+4(1-2x)=5(3-x)
2x-10+4-8x=15-5x
2x-8x+5x=15+10-4
-x=21 (-1)
x=-21
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10y-5(1+y)=3(2y-2)-20
10y-5-5y=6y-6-20
10y-5y-6y=-6-20+5
-y=-21 (-1)
y=21