Solve the System by Using the Inverse of the Coefficient $$\begin{array} { l } 2 x + 8 y + 6 z = 20 \\4 x + 2 y - 2 z = - 2 \\3 x - y + z = 11\end{array}$$

Multiple Choice

Solve the system by using the inverse of the coefficient matrix.
- $$\begin{array} { l } 2 x + 8 y + 6 z = 20 \\4 x + 2 y - 2 z = - 2 \\3 x - y + z = 11\end{array}$$

A) $\{ ( 2,1,6 ) \}$
B) $\varnothing$
C) $\{ ( 2 , - 1,4 ) \}$
D) $\{ ( - 1,2,1 ) \}$