已知x+4y-3z=0 4x-5y+2z=0,xyz不等于0,求3x2+2xy+z2/x2+y2的值

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已知x+4y-3z=04x-5y+2z=0,xyz不等于0,求3x2+2xy+z2/x2+y2的值已知x+4y-3z=04x-5y+2z=0,xyz不等于0,求3x2+2xy+z2/x2+y2的值已知

已知x+4y-3z=0 4x-5y+2z=0,xyz不等于0,求3x2+2xy+z2/x2+y2的值
已知x+4y-3z=0 4x-5y+2z=0,xyz不等于0,求3x2+2xy+z2/x2+y2的值

已知x+4y-3z=0 4x-5y+2z=0,xyz不等于0,求3x2+2xy+z2/x2+y2的值
{x+4y-3z=0 (1)
{4x-5y+2z=0,(2)
(1)×4-(2):
21y-14z=0
∴y=2/3z
那么x+8/3z-3z=0
∴x=1/3z
∴z=3x,y=2x

(3x2+2xy+z2)/(x2+y2)
=(3x^2+2x*2x+9x^2)/(x^2+4x^2)
=(3+4+9)/(1+4)
=16/5