Results 1 to 2 of 2

Math Help - Circle???

  1. #1
    Newbie
    Joined
    Oct 2006
    Posts
    6

    Thumbs down Circle???

    the circle X^2+y^2-2x-3=0 is stretched horizontally by a factor of 2 to obtain an ellipse what is the equaion of this ellipse in genral form

    okay i dont get it!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Global Moderator

    Joined
    Nov 2005
    From
    New York City
    Posts
    10,616
    Thanks
    10
    Quote Originally Posted by andrew93 View Post
    the circle X^2+y^2-2x-3=0 is stretched horizontally by a factor of 2 to obtain an ellipse what is the equaion of this ellipse in genral form

    okay i dont get it!
    Find the standard form,
    (x^2-2x+1)+y^2=4
    (x-1)^2+y^2=4
    Thus a circle of radius 2 centered at (1,0)

    Pretend you have a regular circle of radius 2 and you stech the horizontal by factor of 2 what happends? The ellipse will have a horizontal axis of 4 and vertical axis of 2. The the semi-horizontal and semi-vertical axes, respectively, are. 2,1. In that case the equation of the ellipse is,
    \frac{(x-1)^2}{2^2}+\frac{y^2}{1^2}=1
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Circle, tangent line, and a point not on the circle
    Posted in the Pre-Calculus Forum
    Replies: 5
    Last Post: March 31st 2011, 02:40 PM
  2. Replies: 6
    Last Post: July 8th 2010, 06:39 PM
  3. Replies: 7
    Last Post: March 15th 2010, 05:10 PM
  4. Replies: 2
    Last Post: February 6th 2010, 09:31 AM
  5. Replies: 0
    Last Post: October 12th 2008, 05:31 PM

Search Tags


/mathhelpforum @mathhelpforum