Question

32пункта!!!! СРОЧНО.СПАСИБО

Answer 1

$\left \{ {{x-y+ \sqrt{xy}=20 } \atop {xy=64}} \right. \\ \left \{ {{x-y+ \sqrt{xy}=20 } \atop {\sqrt{xy}=8}} \right. \\ \left \{ {{x-y+8=20} \atop {xy=64}} \right. \\ \left \{ {{x=y+12} \atop {xy=64}} \right. \\ y(y+12)=64\\ y^2=12y-64=0\\ D=144+256=400\\ y1=4\ \ \ \ y2=-16\\ \left \{ {{y1=4} \atop {x1=16}} \right. \ \ \ \ \left \{ {{y2=-16} \atop {x2=-4}} \right.$