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If you mul...
3 years ago
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5 Replies
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Filiberto Rodriguez
5 Answers
opposite the direction of sign
The inequality sign will change to the opposite. For example, < will change to >.
Whenever you multiply or divide an inequality by a negative number, you must flip the inequality sign.
In the following example, notice how the < sign becomes a > sign when the inequality is divided by -2
-2x - 10 < 2
-2x - 10 + 10 < 2 + 10
-2x < 12
x > -6 [Dividing by -2 required the flipping of the inequality sign]
The inequality sign will flip around.
For example:
5x > -3
If you multiply or divide one side by -1 then the sign will flip around so it will become:
-5x < 3
When applying a negative value to an inequality a MAIN rule to note : Swap inequality sign opposite direction when applying a negative value
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