8x+6y+6z=118 2y+1z=20 x+y+z=18 x=5 y=7 z=6 我是

x+y+z=18,8x+6y+6z=118,2y+z=20求解过程 解方程组{x(x+y+z)=6,y(x+y+z)=12,z(x+y+z)=18 (x+y-z)(x-y+z)= {x+y+z=1;x+3y+7z=-1;z+5y+8z=-2 已知x、y、z满足方程组：x+y-z=6；y+z-x=2；z+x-y=0 求x、y、z的值 2x+5y+4z=6,3x+y-7z=-4,x+y-z=? 5x+3y+2z=2011 4x+6y+7z=2012 求x+y+z 已知2x+5y+4z=6 3x+y-7z=-4求x+y-z 若x-y=6,xy=-8,求代数式(x+y+z)²+(x-y-z)(x-y+z)-2·z(x+y)的值 已知x:：y：z=3：4：5,(1)求x+y分之z的值；（2）若x+y+z=6,求x,y,z. 2X+Y+Z=10,X+2Y+Z=-6,X+Y+2Z=8 5X+4Y-3Y=13,2X-3Y+7Z=19,3X-Y=2X 三元一次方程组2x+z=3 3x+y-z=8 x+3y+2z=3 5x+2y-3z=2 x+2y+z=6 7x-2y-4