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Math Help - inequality

  1. #1
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    inequality

    3x + 4 < 5x - 7

    = 3x - 5x < -7 - 4

    = -2x < -11

    = x < 11/2

    correct?? thank u
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  2. #2
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    Quote Originally Posted by jvignacio View Post
    3x + 4 < 5x - 7

    = 3x - 5x < -7 - 4

    = -2x < -11

    = x < 11/2

    correct?? thank u
    Everything was going fine until the end. It's x > 11/2. Why? Because when you multiply by a negative number, the inequality sign changes.

    If c < 0 and a > b, then ca < cb.
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  3. #3
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    Quote Originally Posted by Chop Suey View Post
    Everything was going fine until the end. It's x > 11/2. Why? Because when you multiply by a negative number, the inequality sign changes.

    If c < 0 and a > b, then ca < cb.
    ah yeah i thought so . thank u!
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