Final answer:
To factor the binomial 25x² - 9, use the difference of squares formula to rewrite it as (5x)² - 3², then factor it as (5x + 3)(5x - 3).
Step-by-step explanation:
To factor the binomial 25x² - 9, we can use the difference of squares formula. This formula states that a² - b² can be factored as (a + b)(a - b). In this case, 25x² - 9 can be rewritten as (5x)² - 3². So the factored form is (5x + 3)(5x - 3).
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