Respostas

2014-05-15T08:55:57-03:00
X+y=11
x+2y=14
x=11-y

x+2y=14
(11-y) +2y=14
y=14-11=3

x=11-(3)
x=8

2x+y=
2(8)+1(3)=16+3 = 19