High School

Multiply the polynomials:

[tex](8x^2 + 6x + 8)(6x - 5)[/tex]

A. [tex]48x^3 - 76x^2 + 18x - 40[/tex]

B. [tex]48x^3 - 4x^2 + 78x - 40[/tex]

C. [tex]48x^3 - 4x^2 + 18x - 40[/tex]

D. [tex]48x^3 - 4x^2 + 18x + 40[/tex]

Answer :

To multiply the polynomials [tex]\((8x^2 + 6x + 8)(6x - 5)\)[/tex], we will use the distributive property, also known as the FOIL method for binomials.

1. Distribute each term in the first polynomial to each term in the second polynomial:

[tex]\[(8x^2 + 6x + 8)(6x - 5)\][/tex]

2. Let's start by distributing [tex]\(8x^2\)[/tex]:

[tex]\[8x^2 \cdot (6x - 5) = 48x^3 - 40x^2\][/tex]

3. Next, distribute [tex]\(6x\)[/tex]:

[tex]\[6x \cdot (6x - 5) = 36x^2 - 30x\][/tex]

4. Finally, distribute [tex]\(8\)[/tex]:

[tex]\[8 \cdot (6x - 5) = 48x - 40\][/tex]

5. Now, we combine all these distributed terms:

[tex]\[48x^3 - 40x^2 + 36x^2 - 30x + 48x - 40\][/tex]

6. Combine like terms:

- Combine the [tex]\(x^2\)[/tex] terms: [tex]\(-40x^2 + 36x^2 = -4x^2\)[/tex]
- Combine the [tex]\(x\)[/tex] terms: [tex]\(-30x + 48x = 18x\)[/tex]

So our expression becomes:

[tex]\[48x^3 - 4x^2 + 18x - 40\][/tex]

Therefore, the correct answer is:

C. [tex]\(48 x^3 - 4 x^2 + 18 x - 40\)[/tex]