Развязать систему уравнений . Помогите, пожалуйста)

1)[latex] \left \{ {{x-y=8} \atop {x=9-y}} \right. \left \{ {{x=9-y}\atop {9-y-y=8}} \right. \left \{ {{y=0.5} \atop {x=8.5}} \right. [/latex] 2)[latex] \left \{ {{ log_{2}(x+ y)=log_{2}4} \atop {log_{ \sqrt{3} }xy=log_{ \sqrt{3} }3 \right. \left \{ {{x+y=4} \atop {xy=3 } \right \left \{ {{y=4-x} \atop {x*(4-x)=3}} \right. }} \right. \left \{ {{y=4-x} \atop {x^2-4x+3=0}} \right. \left \{ {{x=1} \atop {x=3}} \right. \left \{ {{x=3} \atop {y=1}} \right. [/latex]