[tex]x-the \ number \ of \ chickens \\ y-the \ number \ of \ rabbits \\ \\ \left \{ {{x+y=16}|(-2) \atop {2x+4y=50}} \right. \\ \\ \\ \left \{ {{-2x-2y=-32} \atop {2x+4y=50} \right. \\..................... \\ / \ \ \ \ \ \ \ 2y=18 => \boxed{y=\frac{18}{2}=9} \\ \\ x+y=16 \\ \\ x+9=16 \\ \\ x=16-9 \\ \\ \boxed{x=7}[/tex]