A teacher received the following answer to a quiz question in which the student was asked to simplify the expression in Step 1:
Step 1: −5(x − 16y) + 7(−2x − 8y)
Step 2: −5x + 80y − 14x − 8y
Step 3: −5x − 14x + 80y − 8y
Step 4: (−14x − 5x) + (80y − 8y)
Step 5: −19x + 72y
Part A: Identify the step where the student made a mistake and explain the specific error that was made. Support your answer using the correct vocabulary. (6 points)
Part B: How would you correct the mistake? Show all your work.
