Factor polynomial $$ c^{2}-81d^{2} $$
Answer
$$ c^{2}-81d^{2} = (c+9d)(c-9d) $$
Explanation
Rewrite $ c^2-81d^2 $ as:
$$ \color{blue}{ c^2-81d^2 = (c)^2 - (9d)^2 } $$Now we can apply the difference of squares formula.
$$ I^2 - II^2 = (I - II)(I + II) $$After putting $ I = c $ and $ II = 9d $ , we have:
$$ c^2-81d^2 = (c)^2 - (9d)^2 = ( c-9d ) ( c+9d ) $$This page was created using
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