Question

{30х + 30у =60
{3х - 3ху = 60; ВИДПОВИДЬ

Answer 1

Объяснение:

$\left \{ {{30x+30y=60\ |:30} \atop {3x-3xy=60\ |:3}} \right.\ \ \ \ \left \{ {{x+y=2} \atop {x-xy=20}} \right. \ \ \ \ \left \{ {{y=2-x} \atop {x-x*(2-x)=20}} \right.\ \ \ \ \left \{ {{y=2-x} \atop {x-2x+x^2=20}} \right. \\\left \{ {{y=2-x} \atop {x^2-x-20=0}} \right.\ \ \ \ \left \{ {{y=2-x} \atop {D=81\ \ \sqrt{D}=9 }} \right. \ \ \ \ \left \{ {{y_1=6\ \ \ \ y_2=-3} \atop {x_1=-4\ \ x_2=5}} \right. .$

Ответ: (-4;6),  (5;-3).