brendanmm brendanmm 13-12-2019 Mathematics contestada If f(x) = 2x - 6 and g(x) = 3x + 9, find (f + g)(x). O A. (f+ g)(x) = x+15 O B. (f+ g)(x) = 5x + 3 O C. (f+ g)(x) = -x - 15 O D. (f+ g)(x) = 5x + 15