[RESOLVED] Solve a cubic polynomial

[Kallog]

I got my quadratic through standard polynomial division of ax^3 + bx^2 + cx + d by (x-r). I also checked it for several values

Ah oops. I didn't notice you're using different coefficient labels to Wikipedia. They divided them all by a and renamed what was left to a,b,c. I'm doing it with only 2 coefficients because that's the form Cardino has it in.