若m-n=4,mn=-1,求代数式(9-2mn+2m+3n)-(3mn+2n-2m)-(m+4n+mn)的值

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若m-n=4,mn=-1,求代数式(9-2mn+2m+3n)-(3mn+2n-2m)-(m+4n+mn)的值

若m-n=4,mn=-1,求代数式(9-2mn+2m+3n)-(3mn+2n-2m)-(m+4n+mn)的值
若m-n=4,mn=-1,求代数式(9-2mn+2m+3n)-(3mn+2n-2m)-(m+4n+mn)的值

若m-n=4,mn=-1,求代数式(9-2mn+2m+3n)-(3mn+2n-2m)-(m+4n+mn)的值
(9-2mn+2m+3n)-(3mn+2n-2m)-(m+4n+mn)
=9-2mn+2m+3n-3mn-2n+2m-m-4n-mn
=9-6mn+3m-3n
=9-6mn+3x(m-n)
=9-6x(-1)+3x4
=9+6+12
=27

化解为
-6mn+3(m-n)+9=27