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2 votes
Marcie solved the following inequality, and her work is shown below:

−2(x − 5) − 12 ≤ 4 + 6(x + 3)
−2x + 10 − 12 ≤ 4 + 6x + 18
−2x − 2 ≤ 6x + 22
−8x ≤ 24
x ≤ −3

What mistake did Marcie make in solving the inequality

User Samjhana
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8.1k points

2 Answers

4 votes
Marcie just left out the 4 on the third line without doing anything to it
User Joel Fischer
by
8.9k points
3 votes
The mistake that Marcie made when solving this inequality was forgetting to switch the inequality sign. When solving an inequality, you sometimes divide by a negative to isolate / solve for the variable. When doing so, the inequality sign flips to its opposite.
User Hulkstance
by
7.9k points
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