Answer: the degree of f(x) is 10
Explanation:
A turning point for a polynomial is a point of the graph where the graph changes from increasing to decreasing or decreasing to increasing.
For a given polynomial f(x) it will always have one less turning point than the degree of the function.
Therefore, for a polynomial with 9 turning points the degree of f(x) is going to be one higher than the number of turning points. So 9+1=10 and the degree of f(x) is 10. The degree of f(x) will be 10 since 10-1= 9 and there are 9 turning points for f(x).