Approach Determination: Determine the approach to factor 25x2−9. We can observe that 25x2 and 9 are both perfect squares, and they are being subtracted from each other. This suggests that we can use the difference of squares formula, which is a2−b2=(a−b)(a+b).
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.
Formula Application: Apply the difference of squares formula to factor the expression.Using the formula a2−b2=(a−b)(a+b), we substitute a with 5x and b with 3.(5x)2−32=(5x−3)(5x+3).
Final Factored Form: Write the final factored form.The factored form of 25x2−9 is (5x−3)(5x+3).
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