Which expression is the factorization of x2 + 10x + 21?

A. (x + 3)(x + 7)
B. (x + 4)(x + 6)
C. (x + 6)(x + 15)
D. (x + 7)(x + 14)
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2 answers

multiply the two numbers in each binomial pair ... you're looking for 21
Which expression is the factorization of x2 + 10x + 21?