Hi !
We have to resolve an equation system to find x and y
[tex]\begin{cases}3x+4y=52\\5x+y=30\end{cases}\\\\\begin{cases}3x-4y=52\\y=30-5x\end{cases}\\\\\\3x+4\times(30-5x)=52\\3x+120-20x=52\\-17x+120=52\\-17x=52-120\\-17x=-68\\\\x=\dfrac{68}{17}\\\\\boxed{x=4}\\\\\\y=30-5\times4\\y=30-20\\\\\boxed{y=10}}\\\\8x-2y=8\times4-2\times10\\8x-2y=32-20\\\\\boxed{8x-2y=12}[/tex]
