SOLUTION: Why does the inequality sign change when both sides are divided and multiplied by a negative number? Does this happen with equations?

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Question 131583: Why does the inequality sign change when both sides are divided and multiplied by a negative number? Does this happen with equations?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Why does the inequality sign change when both sides are divided and multiplied by a negative number? Does this happen with equations?
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Try it with numbers and you will see what happens:
Start: -6 < 18
Multiply both sides by -2
End: 12 > -36
The inequality switched and each of the sides changed sign.
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Start -6 < 18
Divide both sides by -2
End: 3 > -9
Again, the inequality switch and each of the sides changed sign.
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Cheers,
Stan H.