已知m,x,y满足:(x-5)^2+|m|=0,-2ab^y-1与4ab^3的同类项,求(2x^2-3xy+6y^2)-m(3x^2-xy+9y^2)的值快

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已知m,x,y满足:(x-5)^2+|m|=0,-2ab^y-1与4ab^3的同类项,求(2x^2-3xy+6y^2)-m(3x^2-xy+9y^2)的值快已知m,x,y满足:(x-5)^2+|m|=

已知m,x,y满足:(x-5)^2+|m|=0,-2ab^y-1与4ab^3的同类项,求(2x^2-3xy+6y^2)-m(3x^2-xy+9y^2)的值快
已知m,x,y满足:(x-5)^2+|m|=0,-2ab^y-1与4ab^3的同类项,求(2x^2-3xy+6y^2)-m(3x^2-xy+9y^2)的值

已知m,x,y满足:(x-5)^2+|m|=0,-2ab^y-1与4ab^3的同类项,求(2x^2-3xy+6y^2)-m(3x^2-xy+9y^2)的值快
因为(x-5)^2+|m|=0,
(x-5)^2》=0,|m|》=0.
则x-5=0,m=0
x=5,m=0
-2ab^y-1与4ab^3的同类项
则b的指数一定相同
y=3
(2x^2-3xy+6y^2)-m(3x^2-xy+9y^2)
=(2×5^2-3×5×3+6×3^2)-0×(3x^2-xy+9y^2)
=50-45+54
=59