College

What is the product of the polynomials below?

[tex](5x^2 - x - 3)(2x + 6)[/tex]

A. [tex]10x^3 + 28x^2 - 12x - 3[/tex]

B. [tex]10x^3 + 28x^2 + 12x + 3[/tex]

C. [tex]10x^3 + 28x^2 - 12x - 18[/tex]

D. [tex]10x^3 + 28x^2 + 12x + 18[/tex]

Answer :

Sure! Let's find the product of the polynomials [tex]\((5x^2 - x - 3)(2x + 6)\)[/tex] step-by-step.

To do this, we'll use the distributive property, which means each term in the first polynomial should be multiplied by each term in the second polynomial.

1. Distribute [tex]\(5x^2\)[/tex]:

[tex]\[
5x^2 \times 2x = 10x^3
\][/tex]
[tex]\[
5x^2 \times 6 = 30x^2
\][/tex]

2. Distribute [tex]\(-x\)[/tex]:

[tex]\[
-x \times 2x = -2x^2
\][/tex]
[tex]\[
-x \times 6 = -6x
\][/tex]

3. Distribute [tex]\(-3\)[/tex]:

[tex]\[
-3 \times 2x = -6x
\][/tex]
[tex]\[
-3 \times 6 = -18
\][/tex]

Now, combine all these results by adding them together:

[tex]\[
10x^3 + 30x^2 - 2x^2 - 6x - 6x - 18
\][/tex]

4. Combine like terms:

- Combine the [tex]\(x^2\)[/tex] terms: [tex]\(30x^2 - 2x^2 = 28x^2\)[/tex]
- Combine the [tex]\(x\)[/tex] terms: [tex]\(-6x - 6x = -12x\)[/tex]

So, the polynomial simplifies to:

[tex]\[
10x^3 + 28x^2 - 12x - 18
\][/tex]

Therefore, the correct answer is:

C. [tex]\(10x^3 + 28x^2 - 12x - 18\)[/tex]