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    Hi can someone please answer this question for me an explain the steps taken. Im working my way through k a strouds foundation book an he has a worked example but not explained and i cant get my head around it.

    The question is
    y+x/8x - y-x/4x

    Alternatively

    (y+x) (divided by) 8x - (y-x) (divided by) 4x
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    (Original post by Rjamesb)
    Hi can someone please answer this question for me an explain the steps taken. Im working my way through k a strouds foundation book an he has a worked example but not explained and i cant get my head around it.

    The question is
    y+x/8x - y-x/4x

    Alternatively

    (y+x) (divided by) 8x - (y-x) (divided by) 4x
    is it an expression or is there meant to be an answer?
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    (Original post by surina16)
    is it an expression or is there meant to be an answer?
    I think its simplfying
    The final answer is
    3/8 - y/8x
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    (Original post by Rjamesb)
    I think its simplfying
    The final answer is
    3/8 - y/8x
    okay :

    1. to subtract fractions you need a common denominator.
    the denominators are 8x and 4x, and although you would normally cross-multiply, it would be easier here to just multiply the second fraction by 2/2 so you get:
    (y+x)/8x - (2y-2x)/8x
    2. combining this into 1 fraction you get:
    (y + x - 2y + 2x)/8x
    It is +2x because you are subtracting a negative value
    3. simplify the numerator:
    (3x - y)/8x
    I would leave it like this but your book takes it further so:
    4. this is equivalent to:
    3x/8x + -y/8x
    The first fraction simplifies so you get:
    3/8 - y/8x
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    (Original post by surina16)
    okay :

    1. to subtract fractions you need a common denominator.
    the denominators are 8x and 4x, and although you would normally cross-multiply, it would be easier here to just multiply the second fraction by 2/2 so you get:
    (y+x)/8x - (2y-2x)/8x
    2. combining this into 1 fraction you get:
    (y + x - 2y + 2x)/8x
    It is +2x because you are subtracting a negative value
    3. simplify the numerator:
    (3x - y)/8x
    I would leave it like this but your book takes it further so:
    4. this is equivalent to:
    3x/8x + -y/8x
    The first fraction simplifies so you get:
    3/8 - y/8x
    Thanks alot for that, that was a great help
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    (Original post by Rjamesb)
    Thanks alot for that, that was a great help
    no problem! PM me anytime if you need help
 
 
 

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