Respostas

2014-04-11T15:30:29-03:00
X=carros
y=motos
x+y=23
4x+2y=70
x=23-y
4(23-y)+2y=70
92-4y+2y=70
-2y=-22
y=11 motos
x+11=23
x=12 carros.