College

Select the correct answer.

Simplify the expression [tex]-4x^2(3x-7)[/tex].

A. [tex]-12x^3+28[/tex]
B. [tex]-12x^3-28[/tex]
C. [tex]-12x^3-28x^2[/tex]
D. [tex]-12x^3+28x^2[/tex]

Answer :

Let's simplify the expression [tex]\(-4x^2(3x - 7)\)[/tex] step-by-step:

1. Distribute [tex]\(-4x^2\)[/tex] to each term inside the parentheses:

- First term: [tex]\(-4x^2 \times 3x\)[/tex]

Multiply the coefficients [tex]\(-4\)[/tex] and [tex]\(3\)[/tex] to get [tex]\(-12\)[/tex]. Then, multiply the exponents of [tex]\(x\)[/tex] (i.e., [tex]\(x^2 \times x\)[/tex], which equals [tex]\(x^{2+1} = x^3\)[/tex]).

So, [tex]\(-4x^2 \times 3x = -12x^3\)[/tex].

- Second term: [tex]\(-4x^2 \times -7\)[/tex]

Here, multiply the coefficients [tex]\(-4\)[/tex] and [tex]\(-7\)[/tex] to get [tex]\(28\)[/tex]. Since there's no [tex]\(x\)[/tex] in [tex]\(-7\)[/tex], multiply with the remaining [tex]\(x^2\)[/tex].

So, [tex]\(-4x^2 \times -7 = 28x^2\)[/tex].

2. Combine the results:

The expression becomes [tex]\(-12x^3 + 28x^2\)[/tex].

Therefore, the simplified expression is [tex]\(-12x^3 + 28x^2\)[/tex].

The correct answer is:
C. [tex]\(-12x^3 - 28x^2\)[/tex]