Упростите выражение 2x-2y+xy-x2 при x=фото y=фото

$2x-2y+xy-x^2 =2(x-y)-x(-y+x)=2(x-y)-x(x-y)=\\= (x-y)(2-x)=-(x-y)(x-2)$
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$x=-2\frac{1}{7}$ $y=-3\frac{1}{7}$

$-(x-y)(x-2)=-[-2\frac{1}{7}-(-3\frac{1}{7})]*(-2\frac{1}{7}-2)=\\= -[-2\frac{1}{7}+3\frac{1}{7}]*(-2-\frac{1}{7}-2)=\\= -[-2-\frac{1}{7}+3+\frac{1}{7}]*(-4- \frac{1}{7} )=\\= -[1]*(-4\frac{1}{7})=4\frac{1}{7}$