Solve the following equations:
Operating R1→R1-R2, R2→R2-R3
Expanding with C1
0=(x-c)(b-c)(b2-2bc+c2+3bc-x2+2xb-b2-3xb)
0= (x-c)(b-c)(bc+c2-x2-xb)
0=(x-c)(b-c)(-b(-c+x)-(c-x)(-c-x))
0=(x-c)2(b-c)(-b-c-x)
Either x-c=0 or b-c=0 or (-b-c-x)=0
∴x=c or b=c or x=-(b+c)
If b=c, x=b
∴ x=c or x=b or x=-(b+c)