Respuesta :

Answer:

8x² + 5x - 2

Step-by-step explanation:

Given

3x² - 4x + 8 + 5x² + 9x - 10 ← collect like terms

= (3x² + 5x²) + (- 4x + 9x) + (8 - 10)

= 8x² + 5x - 2