$\left\{ \begin{array} { l } x - y + z = 8 \\x + y + z = 6 \\x + y - z = - 12\end{array} \right.$

Multiple Choice

$\left\{ \begin{array} { l } x - y + z = 8 \\x + y + z = 6 \\x + y - z = - 12\end{array} \right.$

A) x=-2, y=-1, z=-9
B) x=2, y=-1, z=9
C) x=-2, y=-1, z=9
D) x=2, y=-1, z=-9