Respuesta :

julie0918

Answer:

-a^2 + ab

Step-by-step explanation:

(a^2 - 2ab +b^2) + (2a^2 + 2ab + b2) = 3a^2 + 2b^2

(a^2 - b^2) + (a^2 + ab + 3b^2) = 2a^2 + 2b^2 + ab

subtract the first part from the second part:

(2a^2 + 2b^2 + ab) - (3a^2 + 2b^2) =    -a^2 + ab