Which expression correctly factors the polynomial? 9x2 - 49 A. (3x – 7)? B. (3x – 7)(3x + 7) C. (9x + 7)(x - 7) D. (9x - 7)(x + 7)

Question

asked Jan 12, 2020 1.3k views

1 Answer

Jucajl · Answer 1 · 2020-01-16T20:34:42+0000

Answer:

B

Explanation:

9x² - 49 ← is a difference of squares and factors in general as

a² - b² = (a - b)(a + b)

Thus

9x² - 49

= (3x)² - 7²

= (3x - 7)(3x + 7) → B