SOLUTION: Why does the inequality sign change when both sides are multiplied or divided by a negative number?

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Question 431528: Why does the inequality sign change when both sides are multiplied or divided by a negative number?
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
Suppose a+%3E+b, and n+%3E+0. From a+%3E+b we obtain a+-+b+%3E+0. We can subtract a-b from both sides to get 0+%3E+-%28a-b%29 --> 0+%3E+-a+%2B+b --> -b+%3E+-a. Finally, we can scale both sides by the same positive number n to get -bn+%3E+-an.