Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Ellipse help

  1. Dec 6, 2008 #1
    1. The problem statement, all variables and given/known data

    q2.jpg

    2. Relevant equations


    given2.jpg

    3. The attempt at a solution

    as2edited.jpg
     
  2. jcsd
  3. Dec 6, 2008 #2
    Re: E-l-l-i-p-s-e h-e-l-p!

    Remember the response I posted earlier:

    1. Plug the points (x, y) into each equation properly.
    2. You got rid of the 1 and didn't use it.
    3. You'll need to solve a system of 2 equations to find a, b.
     
  4. Dec 7, 2008 #3
    Re: E-l-l-i-p-s-e h-e-l-p!

    Thank you :smile:

    Is this correct? ans1.jpg
     
  5. Dec 7, 2008 #4

    HallsofIvy

    User Avatar
    Science Advisor

    Re: E-l-l-i-p-s-e h-e-l-p!

    Check it yourself! It clearly has center (0,0). Do [itex](3, \sqrt{7})[/itex] and [itex]-\sqrt{3},3)[/itex] satisfy that equation? That is, are
    [tex]\frac{3^2}{30}+ \frac{(\sqrt{7})^2}{10}= 1[/tex]
    and
    [tex]\frac{(\sqrt{3})^2}{30}+ \frac{3^2}{10}= 1[/tex] ?

    And don't forget that you were told there were two possible answers. What is the other answer?
     
  6. Dec 7, 2008 #5
    I really don't have an idea... can you give me a hint please? I tried to equate both equation but still I got the same answer...:confused:
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook