Resposta :
3x + y = -2
Y = -2 - 3x
5x + 4 . (-2 -3x) = 9
5x -8 - 12x = 9
5x - 12 = 9 + 8
7x = 17
X = 17/7
Y = - 2 - 3. (17/7)
Y = - 2 - 51/7
Y = -14/ - 51/7
Y = - 65/7
Y = -2 - 3x
5x + 4 . (-2 -3x) = 9
5x -8 - 12x = 9
5x - 12 = 9 + 8
7x = 17
X = 17/7
Y = - 2 - 3. (17/7)
Y = - 2 - 51/7
Y = -14/ - 51/7
Y = - 65/7