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\(\left\{\begin{matrix}2y=33+5x\\-2x-6y=20\end{matrix}\right.\)

\(\left\{\begin{matrix}2y=33+5x\\-2x-6y=20\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}-5x+2y=33\\-2x-6y=20\end{matrix}\right.\text{(Niet verplichte stap, proper schrijven)}\\ \Leftrightarrow \left\{\begin{array}{c|c|c}-5x+2y=33& \color{red}{2.} & \color{blue}{3.} \\-2x-6y=20& \color{red}{-5.} & \color{blue}{1.} \end{array}\right.\\ \Leftrightarrow \left\{\begin{matrix} \color{red}{\underline{-10x+10x}+4y+30y=66-100} \\ \color{blue}{-15x-2x\underline{+6y-6y}=99+20} \end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}34y=-34 \\-17x=119\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}y=\frac{-34}{34}=-1 \\x=\frac{119}{-17}=-7\end{matrix}\right.\\ \qquad V=\{(-7,-1)\}\)