Solve the following equations:

_{Operating R1→R1}-R_2, R_2→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)