Question

Помогите решить третье задание

Answer 1

Ответ:

y = -1;х = 2.

$\left \{ {{2x+2y=2} \atop {3^{x-y} =27}} \right.\\3^{3}=27\\\left \{ {{2(x+y)=2} \atop {x-y=3}}} \right.\\\left \{{{x+y=1} \atop{x-y=3}} \right.\\\left \{ {{y=1-x} \atop {x-(1-x)=3}} \right.\\\left \{ {{y=1-x} \atop {x-1+x=3}} \right.\\\left \{ {{y=1-x} \atop {2x=4}} \right.\\\left \{ {{y=1-x} \atop {x=2}} \right.\\\left \{ {{y=1-2=-1} \atop {x=2}} \right.$