Determine all values of k so that the trinonmial can be factored using integers
I think it might be 10 and 2 but im really not so sure. :/
Help please
Do you know the discriminant ? If yes, then you know that if the discriminant is a perfect square, the quadratic can be factored over the integers. Here the discriminant is equal to :
So, it means that for some , the following holds :
Or, rearranging :
Finally :
Now you can factorize and see which values of actually satisfy this equation. I'm pretty sure you are right with 2 and 10.