Stelsels

Werk uit

\(\left\{\begin{matrix}2x-6y=8\\-8x=5y+84\end{matrix}\right.\)

\(\left\{\begin{matrix}2x-6y=8\\-8x=5y+84\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}2x-6y=8\\-8x-5y=84\end{matrix}\right.\text{(Niet verplichte stap, proper schrijven)}\\ \Leftrightarrow \left\{\begin{array}{c|c|c}2x-6y=8& \color{red}{4.} & \color{blue}{5.} \\-8x-5y=84& \color{red}{1.} & \color{blue}{-6.} \end{array}\right.\\ \Leftrightarrow \left\{\begin{matrix} \color{red}{\underline{8x-8x}-24y-5y=32+84} \\ \color{blue}{10x+48x\underline{-30y+30y}=40-504} \end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}-29y=116 \\58x=-464\end{matrix}\right.\\ \Leftrightarrow \left\{\begin{matrix}y=\frac{116}{-29}=-4 \\x=\frac{-464}{58}=-8\end{matrix}\right.\\ \qquad V=\{(-8,-4)\}\)