SOLUTION: Why do we flip the inequality sign when we divide by a negative number?

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Question 323293: Why do we flip the inequality sign when we divide by a negative number?

Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
Because when you multiply or divide by a negative number, it REVERSES the SIGNS of the numbers involved. What was positive becomes negative, and what was negative becomes positive!!

For example, if you start with

-3 < 12

and divide both sides by -3, now you have

-3/-3 compared to 12/-3
+1 > -4

Dr. Rapalje