Relax

Respuesta :

Answer:

9m(n)^3 +14m(n)^2

Step-by-step explanation:

6m(n)^3 - m(n)^2 + 3m(n)^3 + 15m(n)^2

=> 6m(n)^3 + 3m(n)^3 + 15m(n)^2 - m(n)^2

=> 9m(n)^3 +14m(n)^2