Answer:
sum of the polynomials is [tex]9 x^{3} - 4 x^{2} +3x[/tex]
Step-by-step explanation:
Given polynomial is (7 x^3– 4 x^2) + (2 x^3 +3 x)
adding x^3 terms, now we get
[tex](7+2)x^3-4 x^2+3 x[/tex]
[tex]9 x^{3} - 4 x^2 +3 x[/tex]
Therefore the sum of given polynomial is
[tex]9 x^3-4 x^2+3 x[/tex]