{х+у=9; {х^2-у^2=63
x=9-y => (9-y)^2-y^2=63
81-18y+y^2-y^2=63
81-63=18y
18y=18
y=1 => x=9-1=8
ответ: х=8; у=1.
{х+у=9; {х^2-у^2=63
x=9-y => (9-y)^2-y^2=63
81-18y+y^2-y^2=63
81-63=18y
18y=18
y=1 => x=9-1=8
ответ: х=8; у=1.