Question

17. Factor x ^ 3 + 5x ^ 2 - 9x - 45 . A. (x - 5)(x ^ 2 + 9) b . (x - 5)(x - 3) * (x + 3) Factor By Groupin (x + 5)(x - 3) * (x + 3) d. (x + 5)(x ^ 2 + 9) 5 )

Answer 1

b

Explanation:

Given

x³ + 5x² - 9x - 45 ( factor the first/second and third/fourth terms )

= x²(x + 5) - 9(x + 5) ← factor out (x + 5) from each term

= (x + 5)(x² - 9) ← factor as a difference of squares

= (x + 5)(x - 3)(x + 3)