Question

x^2y+xy^2=6
xy+x+y=3
(система)

Answer 1

$left { {{x^2y+xy^2=6} atop {xy+x+y=3}} right. ; left { {{xy(x+y)=6} atop {xy=3-(x+y)}} right.; left { {{xy=frac{6}{x+y}} atop {xy=3-(x+y)}} right.$
Замена xy = a, x + y = b
$left { {{ab=6} atop {a=3-b}} right. \(3-b)b=6\ b^2-3b+6 = 0;\D < 0$
Решений нет