Factor the expression \(25x^2 - 9\)

Step 1 ：Recognize that \(25x^2 - 9\) is a difference of squares. The expression can be written as \((5x)^2 - 3^2\)

Step 2 ：Apply the formula for factoring a difference of squares. If \(a^2 - b^2\), it can be factored into \((a - b)(a + b)\)

Step 3 ：Substitute \(a = 5x\) and \(b = 3\) into the formula to get the factored form of the expression