Question

What is a polynomial with a single root at x = 8 and a double root at x = 5?

Answer 1

If x=-3 is a root, then x+3=0 and x+3 is a factor of the polynomial.
If x=4 is a root, then x-4=0 and x-4 is a factor of the polynomial
Since this is a double root, there are two factors of (x-4)