25x^2-y^2

The expression \( 25x^2 - y^2 \) is a difference of squares. It can be factored using the difference of squares formula, which states that \( a^2 - b^2 = (a - b)(a + b) \).

In this case:

• \( a^2 = (5x)^2 \) (so \( a = 5x \))
• \( b^2 = y^2 \) (so \( b = y \))

Now, applying the difference of squares formula, we have:

\[ 25x^2 - y^2 = (5x - y)(5x + y) \]

Thus, the factored form of \( 25x^2 - y^2 \) is:

\[ (5x - y)(5x + y) \]