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    Help! Maths paper tomorrow and saw this somewhere on a non-calc paper. I know its probably easy, but i'm sure i'm doing something wrong (keep messing up)

    1/x-2 + 2/x+4 = 1/3

    Solve it someone and show me how to do this in the quickest way!! (before i go mad :eek: )
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    (Original post by shrewd_kitten)
    Help! Maths paper tomorrow and saw this somewhere on a non-calc paper. I know its probably easy, but i'm sure i'm doing something wrong (keep messing up)

    1/x-2 + 2/x+4 = 1/3

    Solve it someone and show me how to do this in the quickest way!! (before i go mad :eek: )
    multiply everything by 3(x-2)(x+4)
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    (Original post by shrewd_kitten)
    Help! Maths paper tomorrow and saw this somewhere on a non-calc paper. I know its probably easy, but i'm sure i'm doing something wrong (keep messing up)

    1/x-2 + 2/x+4 = 1/3

    Solve it someone and show me how to do this in the quickest way!! (before i go mad :eek: )
    [x+4 + 2(x-2)] / (x-2)(x+4) = 1/3

    3x / (x-2)(x+4) = 1/3

    9x = (x-2)(x+4)

    9x = x^2 + 2x -8

    x^2 - 7x - 8 = 0

    (x-8)(x+1) = 0

    Therefore x=8, or x=-1
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    (Original post by shrewd_kitten)
    Help! Maths paper tomorrow and saw this somewhere on a non-calc paper. I know its probably easy, but i'm sure i'm doing something wrong (keep messing up)

    1/x-2 + 2/x+4 = 1/3

    Solve it someone and show me how to do this in the quickest way!! (before i go mad :eek: )
    multiply the left fraction by x+4/x+4 and the right by x-2/x-2 so both denominators are the same then add them together and cross multiply then re-arrange and solve.
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    take all the numbers to one side and keep all the x's on the other side.
    so you get 1/x + 2/x = 7/3
    then you just do the sum.
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    Thanks everyone! my crisis has passed. turns out i was doing it correctly but am just not v. good at factorising (lol..figures..thats prob the easiest bit of the question). I got to the x^2-7x-8 bit and stopped and didn't see how to factorise it (i'm just not a good 'factorisor') anyway, thank you!
 
 
 
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