1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Alegbra 2

  1. Aug 15, 2010 #1
    1. The problem statement, all variables and given/known data

    Express in simplest form.
    1/2 – 4/d divide by 1/d + 3/2d

    2. Relevant equations


    3. The attempt at a solution

    I know the LCD is 2d. But would you multiply this to the equation
  2. jcsd
  3. Aug 15, 2010 #2


    User Avatar
    Gold Member

    You can multiply it as long as you do it to the numerator and the denominator. i.e.:

    \frac{\frac{1}{2}-\frac{4}{d}}{\frac{1}{d}+\frac{3}{2d}} \times \frac{2d}{2d}

    Also, what you have there isn't really an equation. It is only an equation if there is an equals symbol somewhere.
  4. Aug 15, 2010 #3
    Okay, but if you multiply the LCD which is 2d would you multiply 2d to 1/2, 4/d, 1/d and 3/2d

    If so, i got 2d/4d - 8d/2d divided by 2d/2d^2 + 6d/2d^2, is this right?
  5. Aug 15, 2010 #4


    User Avatar
    Gold Member

    Yes you do multiply 2d by 1/2, 4/d, 1/d and 3/2d, but im not quite sure what you have done there.

    [tex]\frac{1}{2}\times 2d = d [/tex]
    [tex]\frac{4}{d}\times 2d = 8 [/tex]
    [tex]\frac{1}{d}\times 2d = 2 [/tex]
    [tex]\frac{3}{2d}\times 2d = 3[/tex]
  6. Aug 15, 2010 #5
    Okay, i understand now. The final answer is d - 8/ 5, thanks a lot
  7. Aug 15, 2010 #6


    User Avatar
    Gold Member

    Yes, that is correct :smile:

    As a side note, you should probably try to pay more attention to use of brackets. d-8/5 could be interpreted as d-(8/5) or as (d-8)/5, which are two completely different expressions.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Threads - Alegbra Date
Boolen alegbra simplification problem Oct 31, 2012
Basic alegbra Sep 18, 2008