Question

Jennifer wrote the following steps to simplify the expression: 3 – (x + 2x – 5).
Step

Mathematical Statement

Justification

0

3 – (x + 2x – 5)

Given

1

3 – x – 2x + 5

Distributive Property

2

3 + 5 – x – 2x

Commutative Property of Addition

3

(3 + 5) + (–x – 2x)

Commutative Property of Addition

4

8 – 3x

Combine Like Terms

Answer 1

Which step of justification is incorrect, and what should the justification for that step be to simplify the expression?

Step 3; Associative Property of Addition

Step 2; Associative Property of Addition

Step 1; Commutative Property of Multiplication

Step 4; Multiplication Property of Equality