Solve the System by Using the Inverse of the Coefficient $$\begin{array} { l } r - 3 s + t = 8 \\- r + 6 s + t = 3 \\3 r - 3 s - t = 6\end{array}$$

Multiple Choice

Solve the system by using the inverse of the coefficient matrix.
- $$\begin{array} { l } r - 3 s + t = 8 \\- r + 6 s + t = 3 \\3 r - 3 s - t = 6\end{array}$$

A) $\left\{ \left( 4 , \frac { 1 } { 3 } , 5 \right) \right\}$
B) $\left\{ \left( - 5 , \frac { 1 } { 3 } , - 4 \right) \right\}$
C) $\left\{ \left( 5 , \frac { 1 } { 3 } , 4 \right) \right\}$
D) $\left\{ \left( - 4 , \frac { 1 } { 3 } , - 5 \right) \right\}$