How do you factor $4x^2 - 64y^2$ ?

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Answer 1 · 2015-07-03T16:42:03

$4x^2 -64 y^2=color(blue)((2x+8y)(2x-8y)$

$4x^2 - 64y^2$ is of the form $color(blue)(a^2 - b^2$ (where $a=2x , b=8y)$ , and as per the identity:
$color(blue)(a^2 - b^2= (a+b)(a-b)$

So, $4x^2 -64 y^2=color(blue)((2x+8y)(2x-8y)$

How do you factor 4x^2 - 64y^24x^2 - 64y^2?