acarson2937 acarson2937 26-06-2018 Mathematics contestada Factor completely 9x2 + 42x + 49. (2 points) a) (3x + 7)(3x − 7) b) (9x − 7)(9x − 7) c) (3x + 7)(3x + 7) d) (9x + 7)(9x + 7)