Problem 29 of 7
Find the first invalid step in this proposed solution: -3x = 12, x = 12 / 3, x = 4.
Hints
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Hidden until you reveal it.
audit equality-preserving moves.
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Solution must contain a clear first invalid equality transformation.
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Correct
Your answer is equivalent to the expected form.
Solution
Walkthrough
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1. Check each transformation in order.
2. Stop at the first step that does not preserve equality.
Use the worked steps, then substitute the final answer back into the original relationship to confirm it satisfies the prompt.
Later errors if an earlier invalid step exists.