In a quadratic trinomial, the first coefficient and the constant term were swapped, after which the result was added to the original trinomial. This resulted in a third quadratic trinomial, which turned out to have a single root. What can this root be equal to? If there are multiple correct answers, list them separated by commas or semicolons.
A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.