Approach Determination: Determine the approach to factor 25x2−9. This expression is a difference of squares because it can be written as a2−b2, where a2 is a perfect square and b2 is a perfect square.
Form Identification: Identify 25x2−9 in the form of a2−b2. 25x2 can be written as (5x)2 because 5x×5x=25x2. 9 can be written as 32 because 3×3=9. So, 25x2−9 can be rewritten as (5x)2−32.
Expression Factoring: Factor the expression using the difference of squares formula.The difference of squares formula is a2−b2=(a−b)(a+b).Applying this formula to our expression, we get:(5x)2−32=(5x−3)(5x+3).
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