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    list all the values of x such that-1<2x<8
    the <8 has a line under it btw
    how do you work this out? i know how to do it for just x by itself but not 2x
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    Oh look, it's the troll again ^.^ Hi!
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    (Original post by p29)
    list all the values of x such that-1<2x<8
    the <8 has a line under it btw
    how do you work this out? i know how to do it for just x by itself but not 2x
    just divide every term by 2 and you're done

    Edit: oh, a troll
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    (Original post by p29)
    list all the values of x such that-1<2x<8
    the <8 has a line under it btw
    how do you work this out? i know how to do it for just x by itself but not 2x
     -\frac{1}{2}&lt;x\leq4

    or you could sketch  y = 2x from the points y = -1 and y = 8 and find the x values in that range...
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    lol im famous
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    im not trolling btw
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    (Original post by DylanJ42)
    just divide every term by 2 and you're done

    Edit: oh, a troll
    so i work out what only x is and then divide every result by 2?
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    X is a letter, silly.
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    (Original post by p29)
    im not trolling btw
    After that double negative nonsense it is hard to take you seriously. No offense.
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    (Original post by RDKGames)
    After that double negative nonsense it is hard to take you seriously. No offense.
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    (Original post by p29)
    Anyway Naruke has given the correct answer above: -1/2 < x <= 4. (The "line under it" makes it greater than or equal to).
    Regarding double negatives: 1 + -1 = 0 by the definition of 0, so -1 * (1 + -1) = 0 by multiplying both sides by -1.
    Now expand the bracket: -1*1 + -1*-1 = 0, and evaluate -1*1 to give -1 + -1*-1 = 0. Now add 1 to both sides to give -1*-1 = 1, as required. It's not difficult to understand.
 
 
 
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