已知x^2+9y^2+4x-6y+5=0,求xy的值 已知m^2+n^2-6m+10n+34=0则m+n=?

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已知x^2+9y^2+4x-6y+5=0,求xy的值 已知m^2+n^2-6m+10n+34=0则m+n=?

已知x^2+9y^2+4x-6y+5=0,求xy的值 已知m^2+n^2-6m+10n+34=0则m+n=?
已知x^2+9y^2+4x-6y+5=0,求xy的值 已知m^2+n^2-6m+10n+34=0则m+n=?

已知x^2+9y^2+4x-6y+5=0,求xy的值 已知m^2+n^2-6m+10n+34=0则m+n=?
因为x^2+9y^2+4x-6y+5=0,所以x^2+4x+4+9y^2-6y+1=0,所以(x-2)^2+(3y-1)^2=0,所以x=2,y=1/3.

因为m^2+n^2-6m+10n+34=0,所以(m-3)^2+(n-5)^2=0,所以m=3,n=5;所以m+n=8.

x²+9y²+4x-6y+5=0
配方后,得(x+2)²+(3y-1)²=0
∴ x+2=3y-1=0
所以,x=-2,y=1/3

m²+n²-6m+10n+34=0
配方后,得(m-3)²+(n+5)²=0
∴ m-3=n+5=0
∴ m=3,n=-5
所以,m+n=3-5=-2

∵x²+9y²+4x-6y+5=0,∴x²+4x+4+9y²-6y+1=0,∴(x+2)²+(3Y-1)²=0.∴x=-2,y=1/3。∴xy=-2/3。
又∵ m²+n²-6m+10n+34=0,∴ m²-6m+9+n²+10n+25=0,∴(m-3)²+(n+5)²=0,∴m=3,n=-5.
∴m+n=-2