Part A: Margie made an error in Step 2.
In Step 2, she added -2.67b and 5.38b instead of subtracting them. She should have subtracted -5.38b instead of adding it.
Part B: To correctly write the expression in fewest terms, we need to subtract -5.38b instead of adding it.
Given: (-2.67b + 11) - (5.38b - 15)
Revised Step 2: -2.67b - 5.38b + 11 + 15
Now, we can combine like terms:
-2.67b - 5.38b = -8.05b
11 + 15 = 26
Final result: -8.05b + 26
Margie's work for adding linear expressions is shown below. After checking her answer with the answer key, she solved it incorrectly.
Given (−2.67b + 11) − (5.38b − 15)
Step 1 −2.67b + 11 + (−5.38b) + 15
Step 2 −2.67b + 5.38b + 11 + 15
Step 3 (−2.67b + 5.38b) + (11 + 15)
Step 4 2.71b + 26
Part A: Identify and explain the first step where Margie made an error. (2 points)
Part B: Explain how to correctly write the expression in fewest terms by correcting the error in Part A. Show all work. (2 points)
1 answer
1 answer