Question

factor.
$81y^2 - 25$

Explanation:

Step1: Identify the form

Notice that \(81y^2 - 25\) is a difference of squares, since \(81y^2=(9y)^2\) and \(25 = 5^2\). The formula for factoring a difference of squares is \(a^2 - b^2=(a + b)(a - b)\).

Step2: Apply the formula

Let \(a = 9y\) and \(b = 5\). Then, substituting into the formula, we get \((9y + 5)(9y - 5)\).

Answer:

\((9y + 5)(9y - 5)\)