Question

find the sum.
\\((4.5x^4 + 3x^3 - x^2 + 6) + (2.6x^4 - 3x + 9) = \square\\)

Explanation:

Step1: Group like terms

$(4.5x^4 + 2.6x^4) + 3x^3 - x^2 - 3x + (6 + 9)$

Step2: Combine $x^4$ terms

$4.5 + 2.6 = 7.1$, so $7.1x^4 + 3x^3 - x^2 - 3x + (6 + 9)$

Step3: Combine constant terms

$6 + 9 = 15$, so $7.1x^4 + 3x^3 - x^2 - 3x + 15$

Answer:

$7.1x^4 + 3x^3 - x^2 - 3x + 15$