已知m,x,y满足2/3(x-5)²+5|m|=0,(2)-2a²b^(y+1)与7a²b³是同类项,求代数式式2x²-6y²+m(xy-9y²)-(3x²-3xy+7y²)的值2x²-6y²+m(y-9y²)-(3x²-3xy+7y²)的值
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已知m,x,y满足2/3(x-5)²+5|m|=0,(2)-2a²b^(y+1)与7a²b³是同类项,求代数式式2x²-6y²+m(xy-9y²)-(3x²-3xy+7y²)的值2x²-6y²+m(y-9y²)-(3x²-3xy+7y²)的值
已知m,x,y满足2/3(x-5)²+5|m|=0,(2)-2a²b^(y+1)与7a²b³是同类项,求代数式
式2x²-6y²+m(xy-9y²)-(3x²-3xy+7y²)的值
2x²-6y²+m(y-9y²)-(3x²-3xy+7y²)的值
已知m,x,y满足2/3(x-5)²+5|m|=0,(2)-2a²b^(y+1)与7a²b³是同类项,求代数式式2x²-6y²+m(xy-9y²)-(3x²-3xy+7y²)的值2x²-6y²+m(y-9y²)-(3x²-3xy+7y²)的值
∵2/3(x-5)^2+5ImI=0
∴x=5,m=0
又-2a^2b^(y+1)与7a^2b^3是同类项,
∴y+1=3
y=2
∴2x^2-6y^2+m(xy-9y^2)-(3x^2-3xy+7y^2)=2x^2-6y^2-3x^2+3xy-7y^2
=-x^2-13y^2+3xy
=-5^2-13*2^2+3*5*2
=-47