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

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

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

已知x+4y-3z=0 4x-5y+2z=0,xyz≠0,求3x²+2xy+z²/x²+y²的值
令z=3,代入方程组得到:
①x+4y=9,
②4x-5y=-6,
解得:x=1,y=2,
再代入原式得:
﹙3×1²+2×1×2+3²﹚/﹙1²+2²﹚
=16/5