Respostas

2013-12-10T11:35:56-02:00
2(5y+1)=27
10y+2=27
10y=27-2
10y=25
y=25/10
y=2,5


2y-3(y-1) = 8-2(y-2)
2y-3y+3=8-2y+4
-y+2y=8+4-3
y=9


1 5 1
2013-12-10T12:02:25-02:00
2(5y+1)=27
2×5y+2×1=27
10y+2=27
10y=27-2
10y= 25
y= 25/10
Simplificando por 5:
y= 5/2 ou 2,5

2y-3(y-1)=8-2(y-2)
2y-3×y-3×(-1)=8-2×y-2×(-2)
2y-3y+3=8-2y+4
2y-3y+2y=8+4-3
y=9


Espero ter ajudado ;D