2 2 9*x + 12*x + 4 - y
9*x^2 + 12*x + 4 - y^2
/ 2 y\ / 2 y\ 1*|x + - + -|*|x + - - -| \ 3 3/ \ 3 3/
(1*(x + (2/3 + y/3)))*(x + (2/3 - y/3))
4.0 - y^2 + 12.0*x + 9.0*x^2
(2 + y + 3*x)*(2 - y + 3*x)