Question

The expression below is the factorization of what trinomial?

(5x + 4)(9x + 9)

A. 45x2 + 81x + 36
B. 14x2 + 13x + 36
C. 45x2 + 13x + 36
D. 14x2 + 81x + 36

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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