求{5x+2y=5 ① y-z=-7 ② 4z+3x=13③的解,速度要写过程

x+y-z=3 y+z-x=5 z+x-y=7 求x,y,z 3x-y=-7,y+2z=2,2x-2z=-5 求x,y,z x/10=y/5=z/7 x+y+2z=29 求x y z 已知2x+5y+4z=6 3x+y-7z=-4求x+y-z 5x+3y+2z=2011 4x+6y+7z=2012 求x+y+z ①X+Y+Z=111②Y:X=3:2③Y:Z=5:4求x,y,z急～ 已知x,y,z均不为0,且满足方程组{x+y-z=0,①2x-y-5z=0.②试求(2x+y+3z)/(3x-y-z)值. 已知x,y,z均不为0,且满足方程组x+y-z=0,①2x-y-5y=0.②试求2x+y+3z/3x-y-z值. 已知:x+y+z=0,5x-3y-z=0,求:5x-y+z/2x+8y+7z 的值 6x+3y-2z=108,9x+7y-3z=212,3x-2y+5z=38,求x,y,z 已知x+y-7z=0 x-2y+5z=0(xyz不等于0）,求x+2y-z/y-2x+12z 已知x+4y+3z=3x-2y-5z=0,求x+2y-z/2x-3y+7z的值 已知4x-3y-6z=0,x+2y-7z=0,求5x+2y-z/2x-3y-10z 已知x.y.z满足x-2y+z=0且7x+4y-5z=0,求x:y:z的值 设z≠0 x、y、z 满足4x-7y-5z=0 2x-y-z=0 求x：y 设z≠0,x、y、z满足4x-7y-5z=0、2x-y-z=0,求x:y 已知x、y、z满足x—2y+z=0 7x+4y—5z=0 ,求x：y：z 已知x,y,z满足方程组x-2y+z=0 7x+4y-5z=0求x:y:z的值