9514 1404 393
Answer:
Step 1: She should have added 25
Explanation:
The second step shows that Erica wanted the result that -25 would disappear from the left side of the equation. However, by subtracting 25, she would end up with -5x - 50 on the left.
To make the sum of -25 and some number be zero, the added number must be the opposite of -25. That is, 25 must be added (to both sides).
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In the attachment, the sum in the red rectangle is -50, not 0.