[x-3/1] [x-5/3] z=31 x未知数

{x+y+z=1;x+3y+7z=-1;z+5y+8z=-2 三元一次方程组,1.x-2y+z=9 2x+y+3z=10 3x+2y1.x-2y+z=92x+y+3z=103x+2y-z2.3x-5y+2z=14x+5y-z=5X-5y+3z=-23.7x+2y-z=76x-y+z=74x+3y+z=94.4x+3y-2z=-75x-6y+z=12x+z=-25.2x+3y-4z=-23x-2y+5z=262x+5z=31 方程组 (1) x+2y-3z=12 x-3y+2z= - 13 x-y-z=0 (2) x+ y=z 5x-y+z=18 2x+5y+3z= -1 x+Y+Z=1 X+3Y+7Z=-1 X+5Y+8Z=2x+Y+Z=1X+3Y+7Z=-1X+5Y+8Z=2 x+2y-z=-5 x+y+2z=-1 3x+4y-2z=-12x+2y-z=3 2x+y+3z=0 4x+z=-4 x+y-z=3 y+z-x=5 z+x-y=7 求x,y,z x+2y+3z=20,x+3y+5z=31,求x+y+z的值 {x+y+z=1 x-2y+3z=5 2x-3y-3z=-8 2x-y+3z=3 {3X+Y-2Z=-1 X+Y+Z=5 1.{x:y:z=3:4:5 2x+3y-5z=-142.{x-y-z=-1 3x+5y+7z=11 4x-y+2z=-13.{x+y=1 x+z=0 2x+y+2z=44.{x-y+z=-3 2x-y-z=-2 -3x+y+z=-15.{x-y+z=-3 3x+y-4z=6 2x+y-z=36.{x-2y+5z=16 2x+y-5z=7 2x-y+z=38 x+y+z=-5,3x+y+z=1,4x+3y+2z=-2快 3x+2y+z=14 ,x+y+z=10,z+2x+3y=1 5 当x;y;z=1;3;5时,x+3y-z除以x-3y+z等于多少? 若x：y：z=1:3:5,求分式x+3y-z/x-3y+z的值 若x:y:z=1：3：5,求x+3y-z/x-3y+Z的值. x-y+z=-1 5x+2y-z=6 4x-3y+2z=-5 {x+y+z=1 {x+3y+7z=-1 {x+5y+8z=2 ｛x-z=-1 2x+y+3z=5 x +y-z=1 怎么解,