Respuesta :

Answer:

Step-by-step explanation:

Combine like terms.Like terms have same variable with same exponent

4x³ + 6x - 7 + 3x³ - 5x² - 5x + 9 = 4x³ + 3x³ - 5x² + 6x - 5x  - 7 + 9

                                                  = 7x³ -5x² + x + 2