# Possible coefficients for a given discriminant

I'm a new user of Sage, and want to know what commands should I use to determine the possible positive definite binary quadratic forms for a given discriminant? i.e the coefficients

For example if I have -47 as a discriminant for a quadratic form, and set [a,b,c]=ax^2+bxy+cy^2, then I will have :

Ro=[1,1,12] , R1=[2,1,6], R2=[3,1,4] , R4=[3,-1,4] , R4=[2,-1,6]