Question 5
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Answer:
x² + 4x + 3
Step-by-step explanation:
Supose answer A is true...
Because the division of
{ (x -5) * (x² + 4x + 3) } / (x -5) = (x² + 4x + 3)
.... you should only have to check if
(x -5) * (x² + 4x + 3) = x³ - x² - 17x - 15
That is what to do:
(x -5) * (x² + 4x + 3)
using FOIL method you get...
x³ + 4x² + 3x - 5x² -20x - 15
x³ + (4x² - 5x²) (-20x + 3x) - 15
and this is exactly x³ - x² - 17x - 15
Hence Answer A is correct.