How do you write #9x^2 – 64# in factored form?

2 Answers
Apr 10, 2018

Answer:

#(3x+8)(3x-8)#

Explanation:

Difference of two squares (DOTS: #a^2-b^2=(a-b)(a+b)#) comes in handy with these sorts of equations

Apr 10, 2018

Answer:

You may see that 9 and 64 are both squares.

Explanation:

Now we may rewrite as:

#=3^2x^2-8^2=(3x)^2-8^2#

And the difference of two squares #A^2-B^2=(A+B)(A-B)#

Or, in this case where A=3x and B=8:

#=(3x+8)(3x-8)#