How do you factor the expression #9x^2 - 4#?

1 Answer
Dec 16, 2015

Answer:

#(3x-2)(3x+2)#

Explanation:

Given: #9x^2-4#

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This is very similar to #(a^2-b^2)# which can be factored into
#(a-b)(a+b)#. So if we can change #9x^2-4# into the standard form of #(a^2-b^2)# we have our solution.

Consider #9x^2#
This can be written as #(3x)^2#

Consider 4
This can be written as #2^2#
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Write as #(3x)^2-2^2# when factored this becomes:

#(3x-2)(3x+2)#