Results 1 to 8 of 8

Math Help - What is the LCD for this complex fraction?

  1. #1
    Junior Member
    Joined
    Feb 2009
    Posts
    31

    What is the LCD for this complex fraction?

    x + 2 - (12 / x + 3) / x - 5 + (16 / x + 3)

    Would the LCD be x(x + 3)? If so, I just multiply the numerator and denominator of this complex fraction by x(x + 3) to find the answer, correct?

    Thanks again!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Senior Member mollymcf2009's Avatar
    Joined
    Jan 2009
    From
    Charleston, SC
    Posts
    490
    Awards
    1
    Quote Originally Posted by Hapa View Post
    x + 2 - (12 / x + 3) / x - 5 + (16 / x + 3)

    Would the LCD be x(x + 3)? If so, I just multiply the numerator and denominator of this complex fraction by x(x + 3) to find the answer, correct?

    Thanks again!
    First let me make sure that I have the right problem:

    \frac{x + 2 - (\frac{12}{x+3})}{x - 5 + (\frac{16}{x+3})}

    Is this what it looks like? Or, in the parentheses is it (\frac{12}{x} + 3)?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Feb 2009
    Posts
    31
    Molly,

    Your first interpretation is correct. My apologies for the confusion.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    10,969
    Thanks
    1009
    Are you trying to simplify this? Or are you just finding an LCM?
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Senior Member mollymcf2009's Avatar
    Joined
    Jan 2009
    From
    Charleston, SC
    Posts
    490
    Awards
    1
    Quote Originally Posted by Hapa View Post
    Molly,

    Your first interpretation is correct. My apologies for the confusion.
    No problem, it happens all the time. Ok, the first thing you should do is get a LCD in the top and bottom of the larger fraction:

    <br />
\frac{x + 2 - (\frac{12}{x+3})}{x - 5 + (\frac{16}{x+3})}

    The LCD in both the top and bottom will be (x+3). Think of the non-fraction numbers as \frac{number}{1}, this will help you see how to evaluate their LCD

    So you will have a fraction over a fraction, with LCD both (x+3). Then, just multiply the top by the reciprocal of the bottom to get rid of the big fraction. This will leave you with a new fraction, which you can multiply out giving you your final LCD

    Good luck!
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Junior Member
    Joined
    Feb 2009
    Posts
    31
    I am trying to simplify this complex fraction.
    Follow Math Help Forum on Facebook and Google+

  7. #7
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    10,969
    Thanks
    1009
    Quote Originally Posted by mollymcf2009 View Post
    No problem, it happens all the time. Ok, the first thing you should do is get a LCD in the top and bottom of the larger fraction:

    <br />
\frac{x + 2 - (\frac{12}{x+3})}{x - 5 + (\frac{16}{x+3})}

    The LCD in both the top and bottom will be (x+3)

    So you will have a fraction over a fraction, with LCD both (x+3). Then, just multiply the top by the reciprocal of the bottom to get rid of the big fraction. This will leave you with a new fraction, which you can multiply out giving you your final LCD

    Good luck!
    Just so there's no confusion...

    \frac{\frac{a}{b}}{\frac{c}{d}} = \frac{a}{b}\div\frac{c}{d}

     = \frac{a}{b}\times \frac{d}{c}.
    Follow Math Help Forum on Facebook and Google+

  8. #8
    MHF Contributor
    Joined
    Mar 2007
    Posts
    1,240

    Talking

    Quote Originally Posted by Hapa View Post
    I am trying to simplify this complex fraction.
    To learn the methodology, try studying one or two online lessons covering how to simplify complex fractions. Make sure you can follow the worked examples.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Complex fraction help
    Posted in the Algebra Forum
    Replies: 3
    Last Post: July 15th 2010, 08:07 PM
  2. Help simplifying a complex fraction
    Posted in the Algebra Forum
    Replies: 4
    Last Post: September 12th 2008, 02:09 AM
  3. Complex Fraction Help
    Posted in the Algebra Forum
    Replies: 3
    Last Post: October 23rd 2007, 07:21 PM
  4. [SOLVED] complex fraction! help!!
    Posted in the Algebra Forum
    Replies: 1
    Last Post: January 11th 2007, 10:48 AM
  5. Complex fraction
    Posted in the Algebra Forum
    Replies: 11
    Last Post: August 1st 2006, 08:00 AM

Search Tags


/mathhelpforum @mathhelpforum