x+y+z=15 x+5y+10z=70 如何算
(x+y-z)(x-y+z)=
X+Y+Z=?
x/2=y/3=z/5 x+3y-z/x-3y+z
若{x+3y+10z=0 则 (x+y-z)/(x-y+z)
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
x+y=10 y+z=15 z+x=20 求x,y,z等于多少?
解方程组x+y-z=-5,x-y-z=1,x-y+z=15
方程组x-y-z=5 y-x-z=1 z-x-y=-15的解是?
若x+3y+5z=10,5x+z+3y=8,x+y+z=?
若X+6Y+4Z=10 4X+4Y+Z=15求X+Y+Z
{5X+Y+Z①X+5Y+Z=-2②X+Y+5Z=10③
matlab如何画z=x^2+y^2,z