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\(\left\{\begin{matrix}6y=-8+5x\\-5x-y=-57\end{matrix}\right.\)

\(\left\{\begin{matrix}6y=-8+5x\\-5x-y=-57\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}-5x+6y=-8\\-5x-y=-57\end{matrix}\right.\text{(Niet verplichte stap, proper schrijven)}\\ \Leftrightarrow \left\{\begin{matrix}-5x+6y=-8\\ -5x+57=y\end{matrix}\right.\text{(Afzonderen onbekende met coëff. 1)}\\ \Leftrightarrow \left\{\begin{matrix}-5x+6\left(-5x+57\right)=-8\\y=-5x+57\end{matrix}\right.\text{(Substitutie!)}\\ \Leftrightarrow \left\{\begin{matrix}-5x-30x+342=-8\\y=-5x+57\end{matrix}\right.\text{(Distributie)}\\ \Leftrightarrow \left\{\begin{matrix}-35x=-8-342=-350\\y=-5x+57\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}x = \frac{-350}{-35} = 10 \\ y=-5x+57\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}x = 10 \\ y=-5.(10)+57=7\end{matrix}\right.\\ \qquad V=\{(10,7)\}\)