Question

A student used the distributive property to simplify 9(m - 4). Their answer was 9m - 4. Which answer choice best describes the student's work?

A - The student correctly simplified. The 9 was distributed to the m and now 4 will be subtracted from the product of 9 and m.

B - The student made an error. The first factor, 9, was distributed to only one of the terms inside the parentheses.

C - The student made an error. 9 should be distributed to the number 4, but not to the variable m.

D - The student made an error. 9 should be distributed to the number 4, but not to the variable m.

(Please help! D: The best answer gets to be thanked and rated!)

Answer 1

The answer is b, 9 was distributed to only one to m, when it needs to be distributed to both.

Answer 2

B

according to distributive law a(b+c) = ab + ac the nominal factor a is distributed, or separately applied, to EACH term of the binomial factor b+c