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Math Help - Inequalities

  1. #1
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    Inequalities

    Find the number of points (x, y), where x and y are non-negative integers, such that
    2x-4\le y \le -3x+40-3y

    Anyone can help?
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  2. #2
    Senior Member DeMath's Avatar
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    Sorry! Wrong
    Last edited by DeMath; August 4th 2009 at 02:47 AM.
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  3. #3
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    I subs. (0,10) and the inequality is still right....

    Strangely, I got infinite numbers of solution...


    EDIT : Ups, not infinite. My rough sketch of the graphs was wrong ^^
    Last edited by songoku; August 4th 2009 at 12:37 AM.
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  4. #4
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    ya..songoku is right, (0, 10) is a possible solution.

    I can solve it graphically, i draw the lines y=2x-4 and 4y=-30x+40

    and find the region satisfying the inequalities. I got 39 points. any other ways to do this?
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  5. #5
    Senior Member DeMath's Avatar
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    Sorry, I understood your task not correct.
    Last edited by DeMath; August 4th 2009 at 02:50 AM. Reason: wrong
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  6. #6
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    Hi DeMath
    Have you tried (0,10) ? ^^
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  7. #7
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    i think you are wrong demath

    if your answer is correct, then (5, 0) is a possible solution,
    But it doesn't satisfy the inequalities...
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