Is there a typo?
The quadratic: . cannot be factored.Solve it by factoring: .
As soon as you mention "Discriminant", you are no longer factoring.The discriminant is positive...
Sure, the solution is quite ugly, but it remains factorisable.
. . You are obviously invoking the Quadratic Formula.
I don't agree . . .But it's false to state what you said...
According to my understanding of "factorable", doesn't factor.
Sure, we can use the Quadratic Formula and get: .
We can say that we have two factors: .
. . but I would not claim that we factored it.
If we include irrational and complex expressions, everything factors.
Oh, I think we just don't agree with the term "factorable"...
There will always be a way to factor it
But I'm not sure to get the reason why it is not factorable in your terms...
Your example of x²-4x+6 shows that we factored it... since we got two factors... whatever the way we used is, isn't it ?
There is also the property :
if a trinomial is factorable, then, it can be written the following way : c(x-a)(x-b).