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\(\left\{\begin{matrix}6x+4y=18\\-6y+8x=-78\end{matrix}\right.\)

\(\left\{\begin{matrix}6x+4y=18\\-6y+8x=-78\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}6x+4y=18\\8x-6y=-78\end{matrix}\right.\text{(Niet verplichte stap, proper schrijven)}\\ \Leftrightarrow \left\{\begin{array}{c|c|c}6x+4y=18& \color{red}{4.} & \color{blue}{3.} \\8x-6y=-78& \color{red}{-3.} & \color{blue}{2.} \end{array}\right.\\ \Leftrightarrow \left\{\begin{matrix} \color{red}{\underline{24x-24x}+16y+18y=72+234} \\ \color{blue}{18x+16x\underline{+12y-12y}=54-156} \end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}34y=306 \\34x=-102\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}y=\frac{306}{34}=9 \\x=\frac{-102}{34}=-3\end{matrix}\right.\\ \qquad V=\{(-3,9)\}\)