>which can have none, 1 or 2 solutions, depending on a, b, c. (In fact, if we're looking for a complex solution, there is always at least one.)
>
Re: ax**2 + bx + c = 0, standard form.
And I might add, for applied solutions you might just want to do a "Discriminant" check, if b**2 - 4*a*c < 0, there are no real solutions, only an imaginary pair. Go back and check your data. (say, what website is this, anyway? :~))