Question

4x-7y=-12 -2x+6y=11

Answer 1

\(\Large \begin{cases} 4x-7y=-12 \ \ \ (1)\\ -2x+6y=11\ \ \ (2) \end{cases}\)

\(\Large (2)\Leftrightarrow -4x+14y=22\) (multiply by 2) \(\Large (3)\)
\(\Large (1)+(3) \Rightarrow 7y=10 \Rightarrow y=\frac{10}{7}\)
From \(\Large (1) \Rightarrow x=\frac{-12+7y}{4}=\frac{-12+10}{4}=\frac{-2}{4}=\frac{-1}{2}\)