Question

Решить систему дам 100 баллов

Answer 1

$\displaystyle \left \{ {{3x^2-6xy+3y^2=4xy} \atop {x-y=6}} \right. \\\left \{ {{3(x^2-2xy+y^2)=4xy} \atop {x-y=6}} \right. \\\left \{ {{3(x-y)^2=4(y+6)y} \atop {x-y=6}} \right.$

3*36=4y²+24y;

4y²+24y-108=0;

y²+6y-27=0;

D=36+4*27=144;

y=(-6+12)/2=3;

y=(-6-12)/2=-9;

x=6+y;

x=9;

x=-3;

Ответ: (9;3); (-3;-9);