Respuesta :

2x + 4y = 8
x = 3y - 6

2x + 4y = 8
2 * ( 3y - 6 ) + 4y = 8
6y + 12 + 4y = 8
8y = 8 - 12
8y = - 4
y = -4 / 8
y = -1 / 2