Giải hệ phương trình \(\left\{ \begin{array}{l}2x - y = 3\\x + y = 3\end{array} \right.\).
A.\(\left ( x;y \right ) = \left ( 2;1 \right )\)
B.\(\left ( x;y \right ) = \left ( 3;1 \right )\)
C.\(\left ( x;y \right ) = \left ( 1;3 \right )\)
D.\(\left ( x;y \right ) = \left ( 1;2 \right )\)