# How do you factor completely #a^2 - 121b^2#?

##### 2 Answers

Jun 13, 2018

#### Answer:

#### Explanation:

The difference of sqares identity can be written:

#A^2-B^2 = (A-B)(A+B)#

Given:

#a^2-121b^2#

Note that both

So we can use the difference of squares identity with

#a^2-121b^2 = a^2-(11b)^2 = (a-11b)(a+11b)#

Jun 13, 2018

#### Answer:

Shown below...

#### Explanation:

Use difference of two squares: