问题标题：
已知X2+Y2+8X+6Y+25=0求代数式X2++XY+4Y2分之X2-4Y2减X+2Y分之X的值
问题描述：
已知X2+Y2+8X+6Y+25=0求代数式X2++XY+4Y2分之X2-4Y2减X+2Y分之X的值
何健刚回答：
X2+Y2+8X+6Y+25=0
x²+8x+16+y²+6y+9=0
(x+4)²+(y+3)²=0
∴x+4=0y+3=0
x=-4y=-3
X2+4XY+4Y2分之X2-4Y2减X+2Y分之X
=(x²-4y²)/(x²+4xy+4y²)-x/(x+2y)
=(x-2y)(x+2y)/(x+2y)²-x/(x+2y)
=(x-2y)/(x+2y)-x/(x+2y)
=(x-2y-x)/(x+2y)
=-2y/(x+2y)
=-2*(-3)/(-4-6)
=-6/(-10)
=3/5
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