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Math Help - inequalities

  1. #1
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    inequalities

    x/8 -1 < -2 = x< -8 question... why doesn't the inequality change. rule says when you devide or multiply an inequality by a negative number you must reverse the
    inequality symbol. please explain why this problem doesn't change
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  2. #2
    Senior Member topher0805's Avatar
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    \frac {x}{8} - 1 < -2

    \frac {x}{8} < -1

    Multiply both sides by 8.

    x < -8

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  3. #3
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    bump

    the question was not the answer I've already givin. the question was why
    doesn't the inequality reverse , knowing the rule is when you multiply or devide by a negative number you reverse the equality.
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  4. #4
    Senior Member topher0805's Avatar
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    Quote Originally Posted by Leona_Marie View Post
    the question was not the answer I've already givin. the question was why
    doesn't the inequality reverse , knowing the rule is when you multiply or devide by a negative number you reverse the equality.
    And I answered the question. It doesn't reverse because you don't multiply or divide by a negative number.
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  5. #5
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    Quote Originally Posted by topher0805 View Post
    \frac {x}{8} - 1 < -2

    \frac {x}{8} < -1

    Multiply both sides by 8.

    x < -8

    I guess I dont know . I thought I was multiplying x/8< -1, could you please try to show more because Im confused
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  6. #6
    Senior Member topher0805's Avatar
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    Quote Originally Posted by Leona_Marie View Post
    I guess I dont know . I thought I was multiplying x/8< -1, could you please try to show more because Im confused
    You are multiplying by 8. 8 is a positive number. Therefore, the inequality stays the same.
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