化简求值x=3,y=1,z=﹣2求﹙x+2y-z﹚﹙x-2y+z﹚-﹙x-2y+z﹚﹙x+2y+z﹚
已知×=负二分之一y=负三分之一z=六分之一求19(x-y+z)的平方减﹣24(x-y-z﹚减112﹙x-y+z﹚的值
已知2分之x=3分之y=4分之z,则3x-2y+z分之2x+y-z=﹙﹚
已知x/2=y/3=z/5,且3x+4z-2y=40,求x、y、z的值﹔详解
解方程组:2x-y+z=6.-3x+2y-z=-9.x+y-2z=-1求解
已知xyz≠0,且x+3y+z=0,2x+3y-z=0 ,求x+2y-7z /3x+5y+z的值?
4x-3y-6z=0,x+2y-7z=0,xyz的积不等于0,求(x+y-z)/(x-y+2z)的值
若x,y,z满足方程租3x+7y-z=3 4x+10y-z=2 求x+y-z
xy/x+y=1,yz/y+z=2,xz/x+z=3求x,y
x-y-z=0 {x+y-3z=4 2x-5y+7z=21 三元一次方程解
已知方程组{2x-y+z=3,3x+4y-z=8,x+y-2z=-3,
已知方程组﹛x+4y-3z=0 4x-5y+2z=0 ,xyz≠0,求﹙3x²+2xy+z²﹚÷﹙x
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,