Respuesta :

GCF of 9 and 21 = 3

9 + 21 =
3(3 + 7) <==

The expression 9x+21 factored using the GCF is 3(3x + 7)

The given expression is:

9x  +  21

The factors of 9x = 1, 3, 9, x, 3x, and 9

The factors of 21 = 1, 3, 7, and 21

Common factors of 9x and 21 = 1 and 3

Greatest Common Factor, GCF, of 9x and 21 = 3

Factoring the GCF out of 9x + 21, the resulting expression becomes:

3(3x  +  7)

Therefore, the expression 9x+21 factored using the GCF is 3(3x + 7)

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