Seudónimo Seudónimo 17-03-2021 Mathematics contestada If we add, 7xy + 5yz – 3zx, 4yz + 9zx – 4y and –3xz + 5x – 2xy, then the answer is: A. 5xy + 9yz +3zx + 5x – 4y B. 5xy + 10yz +3zx + 15x – 4y C. 5xy – 9yz +3zx – 5x – 4y D. 5xy + 10yz +3zx + 5x – 6y