College

What is the sum of the polynomials?

[tex]\left(7x^3 - 4x^2\right) + \left(2x^3 - 4x^2\right)[/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. Group Like Terms:
- Identify terms with the same power of [tex]\(x\)[/tex]. In this case, the terms with [tex]\(x^3\)[/tex] and [tex]\(x^2\)[/tex].

2. Add the Coefficients:
- For [tex]\(x^3\)[/tex] terms: Add the coefficients from both polynomials.
[tex]\[
7x^3 + 2x^3 = (7+2)x^3 = 9x^3
\][/tex]
- For [tex]\(x^2\)[/tex] terms: Add the coefficients from both polynomials.
[tex]\[
-4x^2 + (-4x^2) = (-4-4)x^2 = -8x^2
\][/tex]

3. Write the Result:
- Combine the results from the additions to form the new polynomial.
- The sum is:
[tex]\[
9x^3 - 8x^2
\][/tex]

So, the correct answer is [tex]\(9x^3 - 8x^2\)[/tex]. This corresponds to the option [tex]\(9x^3 -8x^2\)[/tex].