1. Not finding help here? Sign up for a free 30min 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!

Algebra question - quick visual

  1. Oct 26, 2009 #1
    It's a physics question but I need help solving for the radius in the picture bellow
    I need to solve for r so i can finish my physics question off



    http://www.freeimagehosting.net/uploads/th.dc286819a1.jpg


    my work so far

    (r-y)^2 + L^2 = r^2

    r^2 - (2*r*y) + y^2 + L^2 = r^2

    I'm not to sure how to solve this from here
    algebraically, for r
     

    Attached Files:

  2. jcsd
  3. Oct 26, 2009 #2

    lanedance

    User Avatar
    Homework Helper

    subtract r^2 from both sides, then divide everything by -2y
     
  4. Oct 26, 2009 #3
    bah I didn't see how friggen simple it was
    I thought I had to pull out some hardcore mathematics

    If I had continued and just removed r^2 in the first place instead of asking what to do

    -2ry+y^2+l^2
    2ry = y^2 + L^2
    r = (y^2)+(L^2) / 2y

    cheers big ears
     
  5. Oct 27, 2009 #4
    Carefull now. Remember that the 2y is dividing the entire right-hand side, not just the L^2
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Algebra question - quick visual
  1. Algebra question (Replies: 5)

  2. Algebra question (Replies: 15)

  3. Algebra question (Replies: 14)

Loading...