Question

1. $x^2 - 25y^2$

Explanation:

Step1: Recognize difference of squares

The expression $x^2 - 25y^2$ fits $a^2 - b^2$, where $a=x$, $b=5y$ since $(5y)^2=25y^2$.

Step2: Apply difference of squares formula

Use $a^2 - b^2=(a+b)(a-b)$
<Expression>
$x^2 - 25y^2=(x+5y)(x-5y)$
</Expression>

Answer:

$(x+5y)(x-5y)$