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Write the expression 5x(x + 9) − 7(x + 9) in complete factored form.

A.
(x + 9)(x + 9)
B.
(5x − 7)(x + 9)
C.
(5x − 7)(x + 9)(x + 9)
D.
(5x2 + 45x)(-7x − 63)

User Semih Eker
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1 Answer

8 votes
B. (5x-7)(x+9)
This method of factoring is grouping. You could take (x+9) out of both the 5x and the -7, and the next step is putting the 5x -7 in its own set of parentheses.
User Erik Bergstedt
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