Respuesta :

(3x^3 + 4x²) + (3x^3 – 4x^2 – 9x) =​

We have to combine like terms, terms that have x raised to the same power:

First, eliminate the parenthesis:

3x^3 + 4x² + 3x^3 – 4x^2 – 9x =​

We have 2 terms raised to the second power (4x^2 and -4 x^2) simply add and subtract.

3x^3+3x^3+4x^2-4x^2-9x

6x^3-9x

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