Question

unit 7 review assignment
topic 3: factoring polynomials

1. $x^2 - 81$

Explanation:

Step1: Identify the formula

The expression \(x^2 - 81\) is a difference of squares. The formula for factoring a difference of squares is \(a^2 - b^2=(a + b)(a - b)\).

Step2: Apply the formula

Here, \(a = x\) (since \(x^2=a^2\)) and \(b = 9\) (since \(81 = 9^2\)). Substituting into the formula, we get \((x + 9)(x - 9)\).

Answer:

\((x + 9)(x - 9)\)