K773 :a*b^4*c^4*x^2*y - b^3*c^6*x^2*y - a^4*b*c^4*x*y^2 + a^3*c^6*x*y^2 + b^6*c^3*x^2*z - a*b^4*c^4*x^2*z - a^6*c^3*y^2*z + a^4*b*c^4*y^2*z - a^3*b^6*x*z^2 +  a^4*b^4*c*x*z^2 + a^6*b^3*y*z^2 - a^4*b^4*c*y*z^2 = 0