please help on this one?

Answer:
D
Step-by-step explanation:
The factorization of these is ...
A: F(x) = (x -3)(x +3)² . . . . 3 real roots, one with multiplicity 2.
B: F(x) = (x -3)³ . . . . 3 real roots, one with multiplicity 3.
C: F(x) = (x +3)³ . . . . 3 real roots, one with multiplicity 3.
D: F(x) = (x +3)(x² +9) . . . . 1 real root, 2 complex roots.
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Note
A graphing calculator is helpful in factoring these. The quadratic factor of option D was found using synthetic division, after the real root was found using the graphing calculator.