Question 8 (Multiple Choice Worth 2 points)

Factor [tex]\( 15cd - 45c^2d \)[/tex].

A. [tex]\( 3c^2d(5 - 15) \)[/tex]

B. [tex]\( 5cd(3 - 15c^2d) \)[/tex]

C. [tex]\( 3cd(5 - 15c) \)[/tex]

D. [tex]\( 5cd(3 - 9c) \)[/tex]



Answer :

To factor the expression [tex]\( 15cd - 45c^2d \)[/tex] step-by-step, follow these steps:

1. Identify the common factors: Look at the coefficients and the variables in each term of the expression. The terms are [tex]\( 15cd \)[/tex] and [tex]\( 45c^2d \)[/tex].

2. Find the greatest common factor (GCF): The GCF of the numerical coefficients 15 and 45 is 15. Both terms also include the variables [tex]\( c \)[/tex] and [tex]\( d \)[/tex]. Since the first term has [tex]\( c \)[/tex] and the second term has [tex]\( c^2 \)[/tex] (which is [tex]\( c \cdot c \)[/tex]), the GCF for the variable part is [tex]\( c \)[/tex]. Both terms also have the variable [tex]\( d \)[/tex].

So, the GCF of the entire expression is [tex]\( 15cd \)[/tex].

3. Factor out the GCF: Write [tex]\( 15cd \)[/tex] in front of a parenthesis and divide each term by the GCF:

[tex]\[ 15cd \left( \frac{15cd}{15cd} - \frac{45c^2d}{15cd} \right) \][/tex]

4. Simplify inside the parenthesis:
- [tex]\( \frac{15cd}{15cd} = 1 \)[/tex]
- [tex]\( \frac{45c^2d}{15cd} = 3c \)[/tex]

So, the expression inside the parenthesis becomes:

[tex]\[ 1 - 3c \][/tex]

5. Write the final factored form: Combine the factored out GCF with the simplified expression inside the parenthesis:

[tex]\[ 15cd(1 - 3c) \][/tex]

Therefore, the factored form of the expression [tex]\( 15cd - 45c^2d \)[/tex] is:

[tex]\[ 15cd(1 - 3c) \][/tex]

Among the given options, this matches closest to the correct answer. If we look at the options provided:

- [tex]\( 3c^2d(5-15) \)[/tex]
- [tex]\( 5cd(3-15c^2d) \)[/tex]
- [tex]\( 3cd(5-15c) \)[/tex]
- [tex]\( 5cd(3-45c^2d) \)[/tex]

None of these are correct. The closest correct answer should be 15cd(1 - 3c), which unfortunately is not listed among the provided options.

Conclusion: There is a mistake in the provided choices. The correct factorization is indeed [tex]\( 15cd(1 - 3c) \)[/tex], but there's no corresponding option given.