Use a Graphing Utility and Cramer's Rule to Solve (If $$\left\{ \begin{array} { r } x + 2 y - z = - 9 \\2 x - 2 y - 2 z = 0 \\- x + 3 y + 4 z = 0\end{array} \right.$$

Short Answer

Use a graphing utility and Cramer's Rule to solve (if possible) the system of equations.
​ $$\left\{ \begin{array} { r } x + 2 y - z = - 9 \\2 x - 2 y - 2 z = 0 \\- x + 3 y + 4 z = 0\end{array} \right.$$ ​