# How do you factor #4x^2-26#?

##### 1 Answer

May 14, 2016

#### Explanation:

The difference of squares identity can be written:

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

The first term of our expression is a perfect square:

#4x^2 = (2x)^2# .

The second term can be written as a square of its square root:

#26 = (sqrt(26))^2#

Hence we can factor:

#4x^2-26 = (2x)^2-(sqrt(26))^2 = (2x-sqrt(26))(2x+sqrt(26))#