Answer
To solve $$x^{2}-9$$
Let’s use difference of squares
$$(a+3)(a-3)$$
Work Step by Step
SPECIAL FACTORING FORMULAS
Difference of squares
$$(a^{2}-b^{2})=(a+b)(a-b)$$
Perfect squares
$$ (a+b)^{2}=(a^{2}+2ab+b^{2}$$
Sum of Cubes
$$(a^{3}+b^{3})= (a+b)(a^{2}-ab+b^{2})$$
$$x^{2}-9$$
Let’s use difference of squares
$$(a+3)(a-3)$$