解：(x-3y)^2+(3x+y)^2-(x+5y)^2+(x-5y)^2
原式=x²-6xy+9y²+9x²+6xy+y²-x²-10xy-25y²+x²-10xy+15y²
=9x²-10xy+x²-10xy
=10x²-20xy
将x=-2.，y=3代入：
原式=10x²-10xy=40-20*（-2）*3=160
(x-3y)^2+(3x+y)^2-(x+5y)^2+(x-5y)^2
=(x-3y)^2+(y+3x)^2+(x-5y)^2-(x+5y)^2
=x^2-6xy+9y^2+x^2+6xy+9y^2+(x-5y+x+5y)(x-5y-x-5y)
=2x^2+18y^2+(2x)(-10y)
=2x^2+18y^2-20xy
=2(x^2-10xy+9y^2)
=2(x-y)(x-9y)
=2[(-2)-3][(-2)-9x3]
=2(-5)(-2-27)
=2(-5)(-29)
=290
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