Respuesta :

Answer:

9x3 – 8x2

Step-by-step explanation:

Simplify signs:

 

8x2 - 5x3 - 4x2 + 9x3

 

Combine like terms:

 

(8x2 - 4x2) + (9x3 - 5x3)

Answer:

she is correct its is 9x³-8x²

Step-by-step explanation:

Brainliest please