Get the information you need quickly and easily with IDNLearn.com. Our platform is designed to provide reliable and thorough answers to all your questions, no matter the topic.

Select the best answer for the question.

9. Simplify [tex]$(3n - 2m)^2$[/tex]:

A. [tex]$9n^2 - 12mn - 4m^2$[/tex]
B. [tex][tex]$9n^2 + 12mn + 4m^2$[/tex][/tex]
C. [tex]$6n^2 - 12mn - 4m^2$[/tex]
D. [tex]$9n^2 - 12mn + 4m^2$[/tex]


Sagot :

Let's simplify the expression [tex]\((3n - 2m)^2\)[/tex] step-by-step.

First, recall the algebraic identity for the square of a binomial:
[tex]\[ (a - b)^2 = a^2 - 2ab + b^2 \][/tex]

In this case, we can identify [tex]\(a\)[/tex] and [tex]\(b\)[/tex] as follows:
[tex]\[ a = 3n \quad \text{and} \quad b = 2m \][/tex]

Now, applying the identity to our expression:
[tex]\[ (3n - 2m)^2 = (3n)^2 - 2(3n)(2m) + (2m)^2 \][/tex]

Let's calculate each term individually:
1. [tex]\( (3n)^2 = 9n^2 \)[/tex]
2. [tex]\( -2(3n)(2m) = -12mn \)[/tex]
3. [tex]\( (2m)^2 = 4m^2 \)[/tex]

Now, combining these terms together, we get:
[tex]\[ (3n - 2m)^2 = 9n^2 - 12mn + 4m^2 \][/tex]

Therefore, the simplified form of [tex]\((3n - 2m)^2\)[/tex] is:
[tex]\[ 9n^2 - 12mn + 4m^2 \][/tex]

Comparing this result with the given option, we see that the correct answer is:
D. [tex]\(9 n^2 - 12 m n + 4 m^2\)[/tex]