Question

Which one is it........

Answer 1

$\begin{cases}4(x+y)=2x+12\\4x+y=x+8\end{cases}\\\\\\ \begin{cases}4x+4y=2x+12\quad|-2x\\4x+y=x+8\quad|-x\end{cases}\\\\\\ \begin{cases}4x+4y-2x=12\\4x+y-x=8\end{cases}\\\\\\ \boxed{\begin{cases}2x+4y=12\\3x+y=8\end{cases}}$