Системы:х+у/2=1 х-у=3.ху=-14х-у=9.

[latex]\begin{cases}x+\frac{y}{2}=1|*2\\x-y=3\end{cases}<=>\begin{cases}2x+y=2\\+\\x-y=3\end{cases}\\\\3x=5\\x=\frac{5}{3}\\\frac{5}{3}-y=3\\y=-1\frac{1}{3}=-\frac{4}{3}\\OTBET:(\frac{5}{3};-1\frac{1}{3})[/latex] [latex]\begin{cases}xy=-14\\x-y=9=>x=9+y\end{cases}\\y(9+y)=-14\\y^2+9y+14=0\\y_{1,2}=\frac{-9^+_-5}{2}\\y_1=-7\ \ \ \ ;y_2=-2\\x+7=9\ \ \ x+2=9\\x_1=2\ \ \ \ \ \ \ x_2=7\\OTBET:(2;-7);(7;-2)[/latex]