I have a polynomial in $\mathbb{R}[x,y,z]$, say $$p_c(x,y,z)=x^2+y^2+z^2-xyz-c.$$ Do you know any simple piece of software to plot the zeroes of this polynomial using Linux? In the past I plotted similar pictures with Grapher on a Mac, but I really need to do this on a Linux machine.
Thank you!