Respuesta :

gmany

[tex]\left\{\begin{array}{ccc}3x-7y=21\\4x+5y=11\end{array}\right \\\\.\ \ x\qquad y\ \ const.\\\left[\begin{array}{ccc}3&-7\\4&5\end{array}\right|\left\begin{array}{ccc}21\\11\end{array}\right][/tex]