# How do you factor #36n²-9#?

##### 2 Answers

Mar 3, 2016

#### Answer:

#### Explanation:

First we can see that both expressions are divisible by

Next step is to see that in the parenethesis we have the substraction of 2 squares which can be written as:

Mar 3, 2016

#### Answer:

9(2n - 1 )(2n + 1 )

#### Explanation:

First step is to take out common factor of 9.

# 36n^2 - 9 = 9(4n^2 - 1 )# now

# 4n^2 - 1 color(blue) " is a difference of squares "# Consider how this factors:

#a^2 - b^2 = (a - b)(a+b)# hence:

# 4n^2 - 1 = (2n - 1 )(2n + 1 )#