已知x-y=3,xy = -2,求代数式(2x=3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)的值

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已知x-y=3,xy = -2,求代数式(2x=3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)的值

已知x-y=3,xy = -2,求代数式(2x=3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)的值
已知x-y=3,xy = -2,求代数式(2x=3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)的值

已知x-y=3,xy = -2,求代数式(2x=3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)的值
题有问题
(2x=3y-2xy)怎么会是2X=?
原题:
(2x+3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)
(2x+3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)
=2x+3y-2xy-x-4y-xy-(3xy+2y-2x-3)
=x-y-3xy-(3xy+2y-2x-3)
=(x-y)-3xy-【3xy-2(x-y)-3】
=(x-y)-3xy-3xy+2(x-y)+3
=(x-y)-6xy+2(x-y)+3
=3(x-y)-6xy+3
=9+12+3
=24