Factor the expression. \[ 49 n^{2}-25 \]

Step 1 ：Given the expression \(49 n^{2}-25\).

Step 2 ：Recognize this as a difference of squares problem. The difference of squares formula is \(a^2 - b^2 = (a - b)(a + b)\).

Step 3 ：In this case, \(a = 7n\) and \(b = 5\).

Step 4 ：So, we can factor the expression as \((7n - 5)(7n + 5)\).

Step 5 ：\(\boxed{(7n - 5)(7n + 5)}\) is the final answer.