Question

Answer 1

a: \(\Leftrightarrow\left\{{}\begin{matrix}12x=24\\2x-11y=-7\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=2\\y=1\end{matrix}\right.\)

b: \(\Leftrightarrow\left\{{}\begin{matrix}10y=40\\2x+7y=16\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}y=4\\2x=16-7y=-12\end{matrix}\right.\Leftrightarrow\left(x,y\right)=\left(-6;4\right)\)

c: \(\Leftrightarrow\left\{{}\begin{matrix}12x+15y=9\\5x-15y=25\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=2\\y=-1\end{matrix}\right.\)