Answer: D. (x-3)(x-3)
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Explanation:
The last term is 9 and the middle coefficient is -6.
We need to find two numbers that multiply to the last term, and also add to the middle coefficient.
Through trial and error, you should find the two numbers -3 and -3
-3 plus -3 = -6
-3 times -3 = 9
Those two values directly lead to the factorization (x-3)(x-3)
We can FOIL out (x-3)(x-3) to get x^2-6x+9 to help confirm the answer. Distribution works as well. The box method is a visual way to do it also.
