The second is obtained by taking the

cross section of the
heart surface and relabeling the

-coordinates as

, giving the order-6
algebraic equationThe third curve is given by the
parametric equationswhere
![t in [-1,1]](https://lh3.googleusercontent.com/blogger_img_proxy/AEn0k_t5Q9CGZ_8Gt6ohmlzppX2yyNzfF_y4oeUynggsU2TRJ5Ns69JjAtsneTW9TnusaStjAJObgevuqvubVt8gFYexA9jNk0OHwK_i2A3EARgX-YGM97J0nCJ1iqCoEwZRjyPOUSEfBOjn1Q=s0-d)
(H. Dascanio, pers. comm., June 21, 2003). The fourth curve is given by
(P. Kuriscak, pers. comm., Feb. 12, 2006). Each half of this heart curve is a portion of an
algebraic curve of order 6. And the fifth curve is the polar curve