Solve the System of Linear Equations Using Matrices $$\left\{ \begin{array} { r } - x + y = 3 \\- 3 x + y = 7\end{array} \right.$$

Multiple Choice

Solve the system of linear equations using matrices.
- $$\left\{ \begin{array} { r } - x + y = 3 \\- 3 x + y = 7\end{array} \right.$$

A) $( 1 , - 2 )$
B) $( 2 , - 1 )$
C) $( - 2,1 )$
D) $\varnothing$