x^2+y^2+z^2≤6z-4y-2x-14
x^2+2x+1+y^2+4y+4+z^2-6z+9≤0
(x+1)^2+(y+2)^2+(z-3)^2≤0
平方项恒非负,因此
x+1=0 x=-1
y+2=0 y=-2
z-3=0 z=3
x=-1 y=-2 y=3