K751 :

 2*a^4*c^2*x^2*y + 4*a^2*b^2*c^2*x^2*y - 7*b^4*c^2*x^2*y - 
     5*a^2*c^4*x^2*y + 4*b^2*c^4*x^2*y + 2*c^6*x^2*y + 7*a^4*c^2*x*y^2 - 
     4*a^2*b^2*c^2*x*y^2 - 2*b^4*c^2*x*y^2 - 4*a^2*c^4*x*y^2 + 5*b^2*c^4*x*y^2 - 
     2*c^6*x*y^2 - 2*a^4*b^2*x^2*z + 5*a^2*b^4*x^2*z - 2*b^6*x^2*z - 
     4*a^2*b^2*c^2*x^2*z - 4*b^4*c^2*x^2*z + 7*b^2*c^4*x^2*z + 2*a^6*y^2*z - 
     5*a^4*b^2*y^2*z + 2*a^2*b^4*y^2*z + 4*a^4*c^2*y^2*z + 4*a^2*b^2*c^2*y^2*z - 
     7*a^2*c^4*y^2*z - 7*a^4*b^2*x*z^2 + 4*a^2*b^4*x*z^2 + 2*b^6*x*z^2 + 
     4*a^2*b^2*c^2*x*z^2 - 5*b^4*c^2*x*z^2 + 2*b^2*c^4*x*z^2 - 2*a^6*y*z^2 - 
     4*a^4*b^2*y*z^2 + 7*a^2*b^4*y*z^2 + 5*a^4*c^2*y*z^2 - 4*a^2*b^2*c^2*y*z^2 - 
     2*a^2*c^4*y*z^2 =0