College

Multiply the polynomials:

[tex]\left(7x^2 + 9x + 7\right)(9x - 4)[/tex]

A. [tex]63x^3 + 53x^2 + 27x + 28[/tex]

B. [tex]63x^3 + 53x^2 + 59x - 28[/tex]

C. [tex]63x^3 + 81x^2 + 27x - 28[/tex]

D. [tex]63x^3 + 53x^2 + 27x - 28[/tex]

Answer :

Sure! Let's multiply the polynomials step by step:

We want to multiply [tex]\((7x^2 + 9x + 7)(9x - 4)\)[/tex].

### Step 1: Distribute each term in the first polynomial to each term in the second polynomial

Multiply the first term of the first polynomial by each term of the second polynomial:

- [tex]\(7x^2 \cdot 9x = 63x^3\)[/tex]
- [tex]\(7x^2 \cdot (-4) = -28x^2\)[/tex]

Multiply the second term of the first polynomial by each term of the second polynomial:

- [tex]\(9x \cdot 9x = 81x^2\)[/tex]
- [tex]\(9x \cdot (-4) = -36x\)[/tex]

Multiply the third term of the first polynomial by each term of the second polynomial:

- [tex]\(7 \cdot 9x = 63x\)[/tex]
- [tex]\(7 \cdot (-4) = -28\)[/tex]

### Step 2: Combine all the results

Now, we combine all these results together:
- [tex]\(63x^3\)[/tex]
- [tex]\(-28x^2 + 81x^2 = 53x^2\)[/tex]
- [tex]\(-36x + 63x = 27x\)[/tex]
- [tex]\(-28\)[/tex]

### Step 3: Write the final polynomial

So, after combining all like terms, the resulting polynomial is:
[tex]\[ 63x^3 + 53x^2 + 27x - 28 \][/tex]

From the given options, the correct answer is:
D. [tex]\(63x^3 + 53x^2 + 27x - 28\)[/tex]