ahmedretan829 ahmedretan829 23-11-2020 Mathematics contestada 2 What is the sum of 5x2 + 3x - 7 and 12x + 12? A. 5x2 + 15x + 5 B. 5x2 + 15x + 19 C. 17x2 + 3x + 5 D, 17x2 + 15x + 12 4 E. 20x" + 5