Question

The expression below is the factorization of what trinomial?

Answer 1

The answer is:  [A]:   45x² + 81x + 36 .
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Explanation:  Use "FOIL" technique: (First, Outer, Inner, and Last Terms); 
                       then, combine the "like terms", to simplify. 
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(5x+4)(9x+9) = 45x² + 45x + 36x + 35 = 45x² + 81x + 36 .
                                                                       (which is answer choice: "A".).
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