Write the System of Linear Equations as a Matrix Equation $A X = B$

Multiple Choice

Write the system of linear equations as a matrix equation $A X = B$ , and use Gauss-Jordan elimination on the augmented matrix $[ A \vdots B ]$ to solve for the matrix $X$ .
$$\left\{ \begin{aligned}x _ { 1 } + 6 x _ { 2 } + 9 x _ { 3 } & = - 44 \\- 7 x _ { 1 } + 2 x _ { 2 } - x _ { 3 } & = - 54 \\8 x _ { 1 } + 3 x _ { 2 } + 6 x _ { 3 } & = 26\end{aligned} \right.$$

A) $X = \left[ \begin{array} { l } 28 \\ 12 \\ 21 \end{array} \right]$
B) $X = \left[ \begin{array} { c } 12 \\ - 7 \\ - 4 \end{array} \right]$
C) $X = \left[ \begin{array} { c } 7 \\ - 4 \\ - 3 \end{array} \right]$
D) $X = \left[ \begin{array} { l } - 12 \\ - 28 \\ - 21 \end{array} \right]$
E) $X = \left[ \begin{array} { c } - 7 \\ 3 \\ - 4 \end{array} \right]$