giselled977 giselled977 27-09-2022 Mathematics contestada Margie's work for adding linear expressions is shown below. After checking her answer with the answer key, she solved it incorrectly. Given (−4.23b + 13) − (5.47b − 12) Step 1 −4.23b + 13 + (−5.47b) + 12 Step 2 −4.23b + −5.47b + 13 + 12 Step 3 (−4.23b + −5.47b) + (13 + 12) Step 4 9.7b + 25 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)