Answer :
[tex] \left \{ {{-16x-9y=20} \atop {8x+2y=0\ \ | *2}} \right. \\\\ \left \{ {{-16x-9y=20} \atop {16x+4y=0}} \right. \\+------\\\\
-5y=20\ \ \ | divide\ by\ -5\\\\
y=-4\\\\
16x=-4y\ \ \ | divide\ by\ 16\\\\
x=-\frac{1}{4}y=-\frac{1}{4}*(-4)=1[/tex]
