Tawanna is asked to find the GCF of each term in the expression 2 a b + 8 b. Her work is shown below.

Factors of 2ab: 1, 2, a, and b
Factors of 8b: 1, 2, 4, 8, and b
GCF: (1) (1) (2) (2) (b) (b)

Which best describes the error in Tawanna’s solution?
Tawanna factored one or both pieces of the expression incorrectly.
Tawanna did not include each factor in the GCF.
Tawanna should have used each common factor once.
Tawanna included only one of the variables in her solution.

Question

Tawanna is asked to find the GCF of each term in the expression 2 a b + 8 b. Her work is shown below.

Factors of 2ab: 1, 2, a, and b
Factors of 8b: 1, 2, 4, 8, and b
GCF: (1) (1) (2) (2) (b) (b)

Which best describes the error in Tawanna’s solution?
Tawanna factored one or both pieces of the expression incorrectly.
Tawanna did not include each factor in the GCF.
Tawanna should have used each common factor once.
Tawanna included only one of the variables in her solution.

Vocaloid · Answer

Thoughts? The factoring of 2ab and 8b *are* done correctly, but the way the GCF is calculated is incorrect. Did she forget to include factors *or* did she include factors mutiple times? (If there are factors in common between the terms, you only include them once in the GCF)