Results 1 to 5 of 5

Math Help - I am stuck again!

  1. #1
    Member
    Joined
    Aug 2008
    Posts
    182

    Wink I am stuck again!

    mathhelpforum users, I need your help!

    While doing some homework, I got stuck on a few problems.

    Find the simplest equivalent expression for each of the following:


    4xsquared - 64/12xsquared - 60x + 48

    2xsquared - 128/4xsquared - 36x + 32

    Please show how you got the answer, so that I can learn from difficulties.
    Any help will be appreciated!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    Joined
    Jun 2008
    Posts
    792
    Given: 4x^2 - \frac{64}{12}x^2 - 60x + 48

    Multiply by 12 to get rid of the fraction: 48x^2 - 64x^2 - 720x + 576

    Combine the x^2: -16x^2 - 720x + 576

    You can pull -16 as common factor: -16(x^2 + 45x - 36)

    Now do the same for question number 2

    Do you also need to factor?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Super Member

    Joined
    May 2006
    From
    Lexington, MA (USA)
    Posts
    11,751
    Thanks
    651
    Hello, Joker37!


    Please use parentheses when writing fractions . . .



    (4xsquared - 64) / (12xsquared - 60x + 48)
    We have: . \frac{4x^2-64}{12x^2-60x+48}


    Factor . . .

    Numerator: . 4(x^2-16) \:=\:4(x-4)(x+4)

    Denominator: . 12(x^2-5x+4) \:=\:12(x-1)(x-4)


    The fraction becomes: . \frac{4(x-4)(x+4)}{12(x-1)(x-4)}


    Reduce: . \frac{{\color{green}\rlap{/}}4\,{{\color{red}\rlap{//////}}(x-4)}\,(x+4)}{{\color{green}\rlap{//}}12_3\,(x-1)\,{\color{red}\rlap{//////}}(x-4)} \;=\;\boxed{\frac{x+4}{3(x-1)}}




    (2xsquared - 128) / (4xsquared - 36x + 32)
    The same routine . . .

    \frac{2x^2-128}{4x^2-36x + 32} \;=\; \frac{\text{factor}}{\text{factor}} \;=\;\text{Reduce}

    Follow Math Help Forum on Facebook and Google+

  4. #4
    Member
    Joined
    Aug 2008
    Posts
    182

    Smile

    (2xsquared - 128)/(4xsquared - 36x + 32)

    2(xsquared - 64)
    2(xsquared - 8squared)
    2(x - 8)(x + 8)

    4xsquared - 36x + 32
    4(xsquared - 9x +8)
    4(x - 1)(x - 8)

    So, (2(x - 8)(x + 8))/(4x(x - 1)(x - 8))
    = ((x + 8))/(2(x - 1))

    Is this right?

    EDIT: Soz, I forgot the parentheses
    Follow Math Help Forum on Facebook and Google+

  5. #5
    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 Joker37 View Post
    (2xsquared - 128)/(4xsquared - 36x + 32)

    2(xsquared - 64)
    2(xsquared - 8squared)
    2(x - 8)(x + 8)

    4xsquared - 36x + 32
    4(xsquared - 9x +8)
    4(x - 1)(x - 8)

    So, (2(x - 8)(x + 8))/(4x(x - 1)(x - 8))
    = ((x + 8))/(2(x - 1))

    Is this right?

    EDIT: Soz, I forgot the parentheses
    You are correct:

    \frac{x+8}{2(x-1)}
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Stuck
    Posted in the Algebra Forum
    Replies: 6
    Last Post: January 21st 2010, 11:09 AM
  2. stuck with sin^4(x)
    Posted in the Calculus Forum
    Replies: 1
    Last Post: March 24th 2009, 04:56 PM
  3. Stuck on a Log :(
    Posted in the Algebra Forum
    Replies: 9
    Last Post: January 21st 2008, 12:10 PM
  4. somebody help me plz im so stuck
    Posted in the Math Topics Forum
    Replies: 4
    Last Post: September 30th 2007, 11:43 AM
  5. Stuck, Stuck, Stuck - Need Help Urgently
    Posted in the Algebra Forum
    Replies: 3
    Last Post: May 17th 2005, 05:46 AM

Search Tags


/mathhelpforum @mathhelpforum