High School

Simplify the expression:

[tex]
(5x^2 - x^3 - 2x - 1)(-5x - 5)
[/tex]

Then, fill in the following table for multiplication:

[tex]
\begin{array}{|c|c|c|c|c|}
\hline
& 5x^2 & -2x & -x^3 & -1 \\
\hline
-5x & -25x^3 & 10x^2 & 5x^4 & 5x \\
\hline
-5 & -25x^2 & 10x & 5x^3 & 5 \\
\hline
\end{array}
[/tex]

Write the simplified answer in the box below.

Answer :

Sure! Let's simplify the given polynomial expression step-by-step.

The original expression is:
[tex]\((5x^2 - x^3 - 2x - 1)(-5x - 5)\)[/tex]

We will multiply each term in the first polynomial by each term in the second polynomial and then combine like terms.

### Step 1: Distribute each term

1. Multiply [tex]\(-5x\)[/tex] by each term in the first polynomial:
- [tex]\(-5x \times 5x^2 = -25x^3\)[/tex]
- [tex]\(-5x \times -x^3 = 5x^4\)[/tex]
- [tex]\(-5x \times -2x = 10x^2\)[/tex]
- [tex]\(-5x \times -1 = 5x\)[/tex]

2. Multiply [tex]\(-5\)[/tex] by each term in the first polynomial:
- [tex]\(-5 \times 5x^2 = -25x^2\)[/tex]
- [tex]\(-5 \times -x^3 = 5x^3\)[/tex]
- [tex]\(-5 \times -2x = 10x\)[/tex]
- [tex]\(-5 \times -1 = 5\)[/tex]

### Step 2: Combine all the terms

Now, let's organize and combine the like terms from the multiplication:

- For [tex]\(x^4\)[/tex] terms:
- [tex]\(5x^4\)[/tex]

- For [tex]\(x^3\)[/tex] terms:
- [tex]\(-25x^3 + 5x^3 = -20x^3\)[/tex]

- For [tex]\(x^2\)[/tex] terms:
- [tex]\(10x^2 - 25x^2 = -15x^2\)[/tex]

- For [tex]\(x\)[/tex] terms:
- [tex]\(5x + 10x = 15x\)[/tex]

- Constant term:
- [tex]\(5\)[/tex]

### Step 3: Simplified result

So, the simplified expression is:
[tex]\[ 5x^4 - 20x^3 - 15x^2 + 15x + 5 \][/tex]

Therefore, the final expression can be written and factored as:
[tex]\[ 5(x + 1)(x^3 - 5x^2 + 2x + 1) \][/tex]

This is the simplified result of the multiplication of the given polynomials.