Question

решение уровнения х+у=1
ху= -6

Answer 1

$left { {{y+x=1} atop {xy=-6}} right \ left { {{y=1-x} atop {x(1-x)=-6}} right. \ left { {{y=1-x} atop {x-x^2+6=0}} right. \ x^2-x-6=0 \ x_{1}=3 \ x_2 = - 2 \ left { {{y=1-3} atop {x=3}} right. left { {{y=1 + 2} atop {x=-2}} right. \ left { {{y=-2} atop {x=3}} right. left { {{y=3} atop {x=-2}} right.$