Results 1 to 8 of 8

Math Help - Newcomer - Algebra and fraction help.

  1. #1
    Newbie
    Joined
    Jan 2009
    From
    Tˇrshavn
    Posts
    8

    Newcomer - Algebra and fraction help.

    Hello, Im new to this forum and I need a little help with Algebra/fraction. English is not my mother language, so I may confuse some math descriptions.

    Here's my problem:

     <br />
8xy-16x/4xy-8x<br />

    I still need to fix some problems. That is a fraction with algebra.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    Joined
    Dec 2008
    From
    Scotland
    Posts
    901
    Quote Originally Posted by Pingu View Post
    Hello, Im new to this forum and I need a little help with Algebra/fraction. English is not my mother language, so I may confuse some math descriptions.

    Here's my problem:

     <br />
8xy-16x/4xy-8x<br />

    I still need to fix some problems. That is a fraction with algebra.
    If you take out a factor of 2 on the top, then you can write the fraction as:

     \frac{2(4xy-8x)}{4xy-8x}

    Can you see what cancels>?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    A riddle wrapped in an enigma
    masters's Avatar
    Joined
    Jan 2008
    From
    Big Stone Gap, Virginia
    Posts
    2,551
    Thanks
    12
    Awards
    1
    Quote Originally Posted by Pingu View Post
    Hello, Im new to this forum and I need a little help with Algebra/fraction. English is not my mother language, so I may confuse some math descriptions.

    Here's my problem:

     <br />
8xy-16x/4xy-8x<br />

    I still need to fix some problems. That is a fraction with algebra.
    Hello Pingu,

    I'm going to take a guess that this is your expression:

    \frac{8xy-16x}{4xy-8x}

    In the numerator, factor out the common factors of 8x.

    In the denominator, factor out the common factors 4x/

    \frac{8x(y-2)}{4x(y-2)}

    Do you think you can finish up?

    Edit: Mush beat me again as usual, but I factored the thing a bit differently, so I'll leave it. Dang you Mush!
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Newbie
    Joined
    Jan 2009
    From
    Tˇrshavn
    Posts
    8
    Mush and masters: Thanks guys That was just what I needed, but I still need to figure out this MATH code. The fraction was almost as the one I made, but it had "x┤3" and the likes. I will get back, when I get better math coding skills

    EDIT: So, Im back, hehe. This was the original fraction I had problems with:

    \frac{8x^3y-16x^2}{4x^2y-8x}
    Last edited by Pingu; January 13th 2009 at 11:47 AM.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Super Member
    Joined
    Dec 2008
    From
    Scotland
    Posts
    901
    Quote Originally Posted by Pingu View Post
    Mush and masters: Thanks guys That was just what I needed, but I still need to figure out this MATH code. The fraction was almost as the one I made, but it had "x┤3" and the likes. I will get back, when I get better math coding skills
    Do you mean x^{2}.

    If you click on the equations in other people's posts, you can see the code for various things:

    Fractions:

     \frac{a}{b}
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Newbie
    Joined
    Jan 2009
    From
    Tˇrshavn
    Posts
    8
    Quote Originally Posted by Mush View Post
    Do you mean x^{2}.

    If you click on the equations in other people's posts, you can see the code for various things:

    Fractions:

     \frac{a}{b}
    Yes, x^{2}. It was just the ^ I could not find. I have a wierd letter in Faroese (đ) instead of ^.

    Here is another one I had problems with in school today:

     <br />
\frac{2x-4}{3x^2-12}<br />

    If I short it a bit, here is what it comes down to:

     <br />
\frac{2(x-2)}{3(x^2-4)}<br />

    Then:

     <br />
\frac{2(-2)}{3(x-2)}<br />

    And the result?

     <br />
\frac{2}{3x}<br />

    Correct?
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Super Member
    Joined
    Dec 2008
    From
    Scotland
    Posts
    901
    Quote Originally Posted by Pingu View Post
    Yes, x^{2}. It was just the ^ I could not find. I have a wierd letter in Faroese (đ) instead of ^.

    Here is another one I had problems with in school today:

     <br />
\frac{2x-4}{3x^2-12}<br />

    If I short it a bit, here is what it comes down to:

     <br />
\frac{2(x-2)}{3(x^2-4)}<br />

    Then:

     <br />
\frac{2(-2)}{3(x-2)}<br />

    And the result?

     <br />
\frac{2}{3x}<br />

    Correct?
    Not quite!


     <br />
\frac{2(x-2)}{3(x^2-4)}<br />

    This is correct. And from here you should realise that the denominator contains a difference of two squares, and can be written:

     <br />
\frac{2(x-2)}{3(x^2-2^2)}<br />

     <br />
 =\frac{2(x-2)}{3(x+2)(x-2)}<br />

    Then the (x-2) cancels on the top and bottom, leaving:

     <br />
  \frac{2}{3(x+2)}<br />
    Follow Math Help Forum on Facebook and Google+

  8. #8
    Lord of certain Rings
    Isomorphism's Avatar
    Joined
    Dec 2007
    From
    IISc, Bangalore
    Posts
    1,465
    Thanks
    6
    Quote Originally Posted by Pingu View Post
    Yes, x^{2}. It was just the ^ I could not find. I have a wierd letter in Faroese (đ) instead of ^.

    Here is another one I had problems with in school today:

     <br />
\frac{2x-4}{3x^2-12}<br />

    If I short it a bit, here is what it comes down to:

     <br />
\frac{2(x-2)}{3(x^2-4)}<br />

    Then:

     <br />
\frac{2(-2)}{3(x-2)}<br />

    And the result?

     <br />
\frac{2}{3x}<br />

    Correct?
    Pingu,
    Actually usually in such algebraic manipulation problems, its usually easy to figure out if you are wrong. Just substitute a few values for x and check whether both sides of the equations are valid.

    If you are wrong you can try working on the problem again. This method is usually very helpful since you can do it yourself
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Fraction Algebra
    Posted in the Algebra Forum
    Replies: 3
    Last Post: June 1st 2010, 10:20 PM
  2. Basic Fraction Algebra
    Posted in the Algebra Forum
    Replies: 3
    Last Post: June 3rd 2009, 05:48 PM
  3. algebra fraction
    Posted in the Algebra Forum
    Replies: 13
    Last Post: September 22nd 2008, 06:29 PM
  4. algebra fraction
    Posted in the Algebra Forum
    Replies: 2
    Last Post: May 16th 2008, 05:00 AM
  5. Group Theory - newcomer needs help
    Posted in the Advanced Algebra Forum
    Replies: 4
    Last Post: April 26th 2008, 01:05 PM

Search Tags


/mathhelpforum @mathhelpforum