Question

2x - 3y + 4z + 9
2x - 3y = 6
2x= 6

Answer 1

Se
$2x = 6 \\ x = 3$
Então
$2x - 3y = 6 \\ 6 - 3y = 6 \\ y = 0$
E

$2x - 3y + 4z + 9 \\ 6 - 0 + 4z + 9 \\ 15 + 4z \\ 4z = - 15 \\ z = - \frac{15}{4}$