Use the Distributive Property to find which expression is equivalent to 9x^2−25.

A) 9x (x − 25)
B) (3x + 5) ^2
C) (4.5x + 12.5) (4.5x − 12.5)
D) (3x + 5) (3x − 5)

1 answer

To use the Distributive Property to find an equivalent expression for \( 9x^2 - 25 \), we can recognize that this expression is a difference of squares. It can be factored using the identity \( a^2 - b^2 = (a - b)(a + b) \).

In this case, we can rewrite \( 9x^2 - 25 \) as:

\[ (3x)^2 - (5)^2 \]

Applying the difference of squares formula, we have:

\[ 9x^2 - 25 = (3x - 5)(3x + 5) \]

Now, let's look at the options provided:

A) \( 9x(x - 25) \) - This is incorrect.

B) \( (3x + 5)^2 \) - This is incorrect as it expands to \( 9x^2 + 30x + 25 \).

C) \( (4.5x + 12.5)(4.5x - 12.5) \) - This is incorrect, as it expands to \( 20.25x^2 - 156.25 \).

D) \( (3x + 5)(3x - 5) \) - This is correct, as shown above.

Therefore, the correct answer is: D) (3x + 5)(3x - 5).