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\(\left\{\begin{matrix}9y=39+3x\\-8x-7y=-82\end{matrix}\right.\)

\(\left\{\begin{matrix}9y=39+3x\\-8x-7y=-82\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}-3x+9y=39\\-8x-7y=-82\end{matrix}\right.\text{(Niet verplichte stap, proper schrijven)}\\ \Leftrightarrow \left\{\begin{array}{c|c|c}-3x+9y=39& \color{red}{8.} & \color{blue}{7.} \\-8x-7y=-82& \color{red}{-3.} & \color{blue}{9.} \end{array}\right.\\ \Leftrightarrow \left\{\begin{matrix} \color{red}{\underline{-24x+24x}+72y+21y=312+246} \\ \color{blue}{-21x-72x\underline{+63y-63y}=273-738} \end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}93y=558 \\-93x=-465\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}y=\frac{558}{93}=6 \\x=\frac{-465}{-93}=5\end{matrix}\right.\\ \qquad V=\{(5,6)\}\)