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\(\left\{\begin{matrix}-x-2y=-7\\6x+6y=48\end{matrix}\right.\)

\(\left\{\begin{matrix}-x-2y=-7\\6x+6y=48\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}-2y+7=x\\6x+6y=48\end{matrix}\right.\text{(Afzonderen onbekende met coëff. 1)}\\ \Leftrightarrow \left\{\begin{matrix}x=-2y+7\\ 6.\left(-2y+7\right)+6y=48\end{matrix}\right.\text{(Substitutie!)}\\ \Leftrightarrow \left\{\begin{matrix}x=-2y+7\\ -12y+42+6y=48\end{matrix}\right.\text{(Distributie)}\\ \Leftrightarrow \left\{\begin{matrix}x=-2y+7\\ -6y=48-42=6\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}x=-2y+7\\ y=\frac{6}{-6}=-1\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}x=-2.(-1)+7=9\\ y=-1\end{matrix}\right.\\ \qquad V=\{(9,-1)\}\)