How do you factor the expression $9x^2-25$ ?

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Answer 1 · 2016-01-06T04:30:53

$(3x)^2-(5)^2=(3x+5)(3x-5)$

$9x^2-25$ fits the form $a^2-b^2$ , where $a=3x$ and $b=5$ . Rewrite the expression as $(3x)^2-(5)^2$ .

Use the difference of squares: $a^2-b^2=(a+b)(a-b)$ .

$(3x)^2-(5)^2=(3x+5)(3x-5)$

How do you factor the expression 9x^2-259x^2-25?