# How do you factor #x^2-9#?

##### 2 Answers

Mar 20, 2018

#### Explanation:

#x^2-9" is a "color(blue)"difference of squares"#

#"and in general factorises as"#

#•color(white)(x)a^2-b^2=(a-b)(a+b)#

#"here "a=x" and "b=3#

#rArrx^2-9=(x-3)(x+3)#

Mar 20, 2018

See a solution process below:

#### Explanation:

This is a special case of the quadratic: