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How To Simplify?? (6 marks!) Watch

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    How do you do this question? Can you go through it step by step?

    Thanks!

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    Add the fractions

    Multiply by the denominator

    Cancel by 100

    Collect on one side
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    Have you tried multiplying by  5 - x and  5 + x ?
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    (Original post by TenOfThem)
    Add the fractions

    Multiply by the denominator

    Cancel by 100

    Collect on one side
    Why add if it's minus?

    Yeah I know cross multiplying It just doesn't get the correct answer

    Ps can you help me on my other expression question? You're amazing at maths and with your explanation, I will def understand it!
    (Original post by Groat)
    Have you tried multiplying by  5 - x and  5 + x ?
    Yes!
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    (Original post by blueray)
    How do you do this question? Can you go through it step by step?

    Thanks!

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    Divide throughout by 100.

    Get both fraction over a common denominator.

    Example:

     \displaystyle \frac{100}{x+1} + \frac{100}{x-1} = 10 \implies \frac{10}{x+1} + \frac{10}{x-1} = 1 \\ \implies \frac{10(x-1)}{(x+1)(x-1)} + \frac{10(x+1)}{(x-1)(x+1)} = 10 \\ \implies \frac{10(x-1)+10(x+1)}{(x+1)(x-1)} = 1 \\ \implies 10(x-1)+10(x+1) = (x+1)(x-1)
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    (Original post by blueray)
    Why add if it's minus?

    Yeah I know cross multiplying It just doesn't get the correct answer

    Ps can you help me on my other expression question? You're amazing at maths and with your explanation, I will def understand it!


    Yes!
    Where have you got so far? Which part of your working are you stuck at?
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    (Original post by blueray)
    Why add if it's minus?

    Well ... subtract then ... but that is just adding a negative so my post holds
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    (Original post by tyre)
    ...
    Please don't post full solutions. Click here for guidelines to posting in the maths forum.
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    I have learnt how to do it thanks! I just cross multiply it! I accidently put the x and 5 wrong way, so I was mixed up. Sorry!

    (Original post by nuodai)
    Please don't post full solutions. Click here for guidelines to posting in the maths forum.
    No please, it's fine. In my case I really do need the solution, it doesn't matter, because I have the mark scheme, I just need clarification on it. So please don't remove next time! Thanks!
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    (Original post by TenOfThem)
    Add the fractions

    Multiply by the denominator

    Cancel by 100

    Collect on one side

    (Original post by Groat)
    Have you tried multiplying by  5 - x and  5 + x ?

    (Original post by raheem94)
    Divide throughout by 100.

    Get both fraction over a common denominator.

    Example:

     \displaystyle \frac{100}{x+1} + \frac{100}{x-1} = 10 \implies \frac{10}{x+1} + \frac{10}{x-1} = 1 \\ \implies \frac{10(x-1)}{(x+1)(x-1)} + \frac{10(x+1)}{(x-1)(x+1)} = 10 \\ \implies \frac{10(x-1)+10(x+1)}{(x+1)(x-1)} = 1 \\ \implies 10(x-1)+10(x+1) = (x+1)(x-1)

    (Original post by tyre)
    (Removed by moderator.)

    (Original post by nuodai)
    Please don't post full solutions. Click here for guidelines to posting in the maths forum.
    Can anyone of you help me on this question?

    http://www.thestudentroom.co.uk/show....php?t=1991188

    Thank you!
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    (Original post by blueray)
    No please, it's fine. In my case I really do need the solution, it doesn't matter, because I have the mark scheme, I just need clarification on it. So please don't remove next time! Thanks!
    (Original post by blueray)
    Can anyone of you help me on this question?

    http://www.thestudentroom.co.uk/show....php?t=1991188

    Thank you!
    All you have to do is follow raheem94's solution line-for-line, but changing the numbers as appropriate, and you'll get your answer. If you're still stuck, show your working and we'll help you get there. It won't take much work to do this, but you'll learn much more from it than you would from copying out a solution line-for-line without having to think about it at all.
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    (Original post by nuodai)
    Please don't post full solutions. Click here for guidelines to posting in the maths forum.
    Sorry for you getting a neg rep for abiding with the laws, the rep system is flawed in my opinion.
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    (Original post by raheem94)
    Sorry for you getting a neg rep for abiding with the laws, the rep system is flawed in my opinion.
    People are welcome to give me neg rep if they think I've done something wrong. (If anything, rep whether pos or neg will help me work out whether or not I'm screwing up this newfangled 'moderator' thing or not!)

    But in this case I'm quite sure of my position: the full solution, albeit correct, was a cop-out for the OP and undermined the effort that other users had put into trying to help the OP actually develop maths skills rather than copying-out skills.
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    (Original post by nuodai)
    People are welcome to give me neg rep if they think I've done something wrong. (If anything, rep whether pos or neg will help me work out whether or not I'm screwing up this newfangled 'moderator' thing or not!)
    But your neg rep was undeserved. It won't allow me to +rep you to cancel that out.

    By the way, congrats for becoming a moderator!
    :congrats:
 
 
 
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