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    5X + 2Y 2X - 3Y
    ------- _ ---------
    4...............5

    = 5(5X + 2Y) - 4(2X-3Y)
    ------------------------
    20

    = 25X + 10Y - 8X +12Y
    -------------------------
    20

    = 22Y + 17X
    ------------
    20

    Where did I go wrong?

    Thanks.
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    In the first line, you have \dfrac{5x+2x}{4}(=\dfrac{7x}{4}) at the begining. Either this is a typo, or if not, then the second line is where the mistake is, because you've misread X as Y.

    Here:
    (Original post by tempa)
    5X + 2X _ 2X -3Y
    --------- ---------
    4.................. 5
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    My eyes
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    5X + 2X _ 2X -3Y
    --------- ---------
    4.................. 5

    is this bit supposed to be

    5X + 2Y _ 2X -3Y
    --------- ---------
    4.................. 5

    ?
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    Sorry,

    My mistake.

    5X + 2Y 2X - 3Y
    ------- _ ---------
    4...............5
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    I get the same answer as you.
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    Yeah im crap at maths nvm xD
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    - 4 : I thought the - sign is with the 4 therefore I -4 x -3y = 12y?
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    i get same answer as you OP, really doubt you've gone wrong anywhere
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    My teacher marked it as wrong
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    (Original post by Tempa)
    My teacher marked it as wrong
    It isn't.
    Unless, was that the whole question? Or did you get to the first line from some other, earlier parts?
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    (Original post by foolsihboy)
    It isn't.
    Unless, was that the whole question? Or did you get to the first line from some other, earlier parts?

    5X + 2Y 2X - 3Y
    ------- _ ---------
    4...............5

    This the question. :P
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    (Original post by Tempa)
    5X + 2Y 2X - 3Y
    ------- _ ---------
    4...............5

    This the question. :P
    As in \dfrac{5x+2y}{4} - \dfrac{2x-3y}{5} ??

    This does, as in your OP, simplify to

    \dfrac{17x+22y}{20}.

    Perhaps your teacher was tired? Or misread it? Or just made a mistake. They have to mark many sheets you know...
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    Ok boss as you are doing a degree in mathematics I'll take your word for it.
    Thanks.
 
 
 
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