Question

question 2 of 10
what is the product of (5x + 1)(5x - 1)?

a. 10x² - 1
b. 10x² + 10x - 1
c. 25x² - 1
d. 25x² + 10x - 1

Explanation:

Step1: Identify the formula

This is a difference of squares: \((a + b)(a - b) = a^2 - b^2\). Here, \(a = 5x\) and \(b = 1\).

Step2: Apply the formula

Calculate \(a^2\) and \(b^2\):

• \(a^2 = (5x)^2 = 25x^2\)
• \(b^2 = 1^2 = 1\)

So, \((5x + 1)(5x - 1) = (5x)^2 - 1^2 = 25x^2 - 1\).

Answer:

C. \(25x^2 - 1\)