Factor polynomial $$ a^{2}-9 $$
Answer
$$ a^{2}-9 = ( a-3 )( a+3 ) $$
Explanation
Rewrite $ a^{2}-9 $ as:
$$ a^{2}-9 = (a)^2 - (3)^2 $$Now we can apply the difference of squares formula.
$$ I^2 - II^2 = (I - II)(I + II) $$After putting $ I = a $ and $ II = 3 $ , we have:
$$ a^{2}-9 = (a)^2 - (3)^2 = ( a-3 ) ( a+3 ) $$This page was created using
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