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\(\left\{\begin{matrix}-5x-6y=65\\-x=5y+51\end{matrix}\right.\)

\(\left\{\begin{matrix}-5x-6y=65\\-x=5y+51\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}-5x-6y=65\\-x-5y=51\end{matrix}\right.\text{(Niet verplichte stap, proper schrijven)}\\ \Leftrightarrow \left\{\begin{matrix}-5x-6y=65\\ -5y-51=x\end{matrix}\right.\text{(Afzonderen onbekende met coëff. 1)}\\ \Leftrightarrow \left\{\begin{matrix}-5\left(-5y-51\right)-6y=65\\x=-5y-51\end{matrix}\right.\text{(Substitutie!)}\\ \Leftrightarrow \left\{\begin{matrix}25y+255-6y=65\\x=-5y-51\end{matrix}\right.\text{(Distributie)}\\ \Leftrightarrow \left\{\begin{matrix}19y=65-255=-190\\x=-5y-51\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}y = \frac{-190}{19} = -10 \\ x=-5y-51\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}y = -10 \\ x=-5.(-10)-51=-1\end{matrix}\right.\\ \qquad V=\{(-1,-10)\}\)