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\(\left\{\begin{matrix}-6y=-108+6x\\x+4y=42\end{matrix}\right.\)

\(\left\{\begin{matrix}-6y=-108+6x\\x+4y=42\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}-6x-6y=-108\\x+4y=42\end{matrix}\right.\text{(Niet verplichte stap, proper schrijven)}\\ \Leftrightarrow \left\{\begin{matrix}-6x-6y=-108\\ x=-4y+42\end{matrix}\right.\text{(Afzonderen onbekende met coëff. 1)}\\ \Leftrightarrow \left\{\begin{matrix}-6\left(-4y+42\right)-6y=-108\\x=-4y+42\end{matrix}\right.\text{(Substitutie!)}\\ \Leftrightarrow \left\{\begin{matrix}24y-252-6y=-108\\x=-4y+42\end{matrix}\right.\text{(Distributie)}\\ \Leftrightarrow \left\{\begin{matrix}18y=-108+252=144\\x=-4y+42\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}y = \frac{144}{18} = 8 \\ x=-4y+42\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}y = 8 \\ x=-4.(8)+42=10\end{matrix}\right.\\ \qquad V=\{(10,8)\}\)