# How do I define the elliptic curve: y^2 + y = x^3 - x^2 on Sage 9.3?

The elliptic curve construction function takes only constants as inputs. But I want to define an elliptic curve E who's equation is given above.

Thank you.

Typing

`EllipticCurve?`

in a Sage console or notebook (possibly completed with a helping of Wikipedia) may illuminate you... and explain :