College

What is the sum of the polynomials?

[tex](7x^3 - 4x^2) + (2x^3 - 4x^2)[/tex]

A. [tex]5x^3[/tex]
B. [tex]9x^3[/tex]
C. [tex]5x^3 - 8x^2[/tex]
D. [tex]9x^3 - 8x^2[/tex]

Answer :

To find the sum of the polynomials [tex]\((7x^3 - 4x^2) + (2x^3 - 4x^2)\)[/tex], follow these steps:

1. Combine like terms:
- Start by looking at the [tex]\(x^3\)[/tex] terms: You have [tex]\(7x^3\)[/tex] from the first polynomial and [tex]\(2x^3\)[/tex] from the second. Add these together:
[tex]\[
7x^3 + 2x^3 = 9x^3
\][/tex]

2. Do the same with the [tex]\(x^2\)[/tex] terms:
- Look at the [tex]\(x^2\)[/tex] terms: You have [tex]\(-4x^2\)[/tex] from the first polynomial and [tex]\(-4x^2\)[/tex] from the second. Add these together:
[tex]\[
-4x^2 + (-4x^2) = -8x^2
\][/tex]

3. Write the resulting polynomial:
- After combining all like terms, you end up with the polynomial:
[tex]\[
9x^3 - 8x^2
\][/tex]

So, the sum of the polynomials [tex]\((7x^3 - 4x^2) + (2x^3 - 4x^2)\)[/tex] is [tex]\(\boxed{9x^3 - 8x^2}\)[/tex].