Question

Josh is trying to factor the expression -20a - 8.4 + 12.8b. He writes -4(5a + 2.1 + 3.2b).

a. What error did Josh likely make?

b. Factor the expression correctly.

c. Write an equivalent factored expression

Answer 1

Answer: =)

Explanation:

a. The error Josh made in the problem is that he used a +3.2b. He was supposed to use -3.2b. Why? because the expression is -20a -8.4 + 12.8b, and he used -4 to make the equivalent factored expression. when you multiply +3.2 and a -4, the answer will turn out to be a negative number.

b. -20a -8.4 + 12.8b

c. The correct equivalent factored expression would be -4(5a + 2.1 -3.2b)

Answer 2

a. The error Josh makes is that he puts +3.2b when it’s supposed to be -3.2b because 12.8/-4 is -3.2b

b. -4(5a + 2.1 - 3.2)

c. -20a + 4.4