Answer:
Short Answer: B
Explanation:
Using synthetic division to break this down a little, we get from your hint, the following
-5 || 1 - 4 -21 100 - 100
-5 45 -120 100
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1 -9 24 -20 0 = x^3 - 9x^2 + 24x - 20
We can do this again, this time using 5
5 || 1 - 9 24 - 20
5 -20 20
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1 -4 4 0 = x^2 - 4x + 4
h(x) = x^2 - 4x + 4 factors into
h(x) = (x - 2)(x - 2)
The final result is f(x) = (x + 5)(x - 5)(x - 2) (x - 2)
which is B