Respostas

2014-08-11T14:49:26-03:00
10y - 5(1 + y) = 3(2y - 2) - 20
10y - 5 - 5y = 6y - 6 - 20
5y - 5 = 6y - 26
y = 21
2014-08-11T14:51:12-03:00
10y-5(1+y)=3(2y-2)-20
10y -5 -5y = 6y -6 -20
y = 21