Results 1 to 5 of 5

Math Help - Equation of a circle

  1. #1
    Newbie
    Joined
    Oct 2009
    Posts
    21

    Question Equation of a circle

    guys can you help me answer this question and explain how to solve it
    Find the equation of a circle given the center is (3, -2) and it is tangent to the x-axis; what about if it is tangent to y-axis
    Last edited by FailCalculus; November 14th 2009 at 06:10 AM.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Member
    Joined
    Oct 2009
    Posts
    147
    Thanks
    1
    if it is tangent to both axes as you said, that centre should be (3, -3) or (2, -2)....isn't it???
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Super Member

    Joined
    May 2006
    From
    Lexington, MA (USA)
    Posts
    11,903
    Thanks
    764
    Hello, FailCalculus!

    Please check the wording of the problem.
    As stated, there is no solution.


    Find the equation of a circle given the center is (3, -2)
    and is tangent to the x-axis and tangent to y-axis

    The center is at (3, -2).
    Code:
            |
            |           3
        ----+-----------+---
            |           :
            |           :
            |           :
         -2 + - - - - - *
            |

    The center is 2 units from the x-axis
    - - - - . . and 3 units from the y-axis.

    Quite impossible!

    Follow Math Help Forum on Facebook and Google+

  4. #4
    Newbie
    Joined
    Oct 2009
    Posts
    21
    Quote Originally Posted by ukorov View Post
    if it is tangent to both axes as you said, that centre should be (3, -3) or (2, -2)....isn't it???
    Quote Originally Posted by Soroban View Post
    Hello, FailCalculus!

    Please check the wording of the problem.
    As stated, there is no solution.



    The center is at (3, -2).
    Code:
            |
            |           3
        ----+-----------+---
            |           :
            |           :
            |           :
         -2 + - - - - - *
            |

    The center is 2 units from the x-axis
    - - - - . . and 3 units from the y-axis.

    Quite impossible!

    guys im sorry i've check the problem and i admit that i type it wrong . i've already edit it . thanks to both of you
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Member
    Joined
    Oct 2009
    Posts
    147
    Thanks
    1
    For a circle with centre (3, -2) and radius r = 2 units,
    (x - 3)^2 + (y + 2)^2 = 2^2
    x^2 - 6x + 9 + y^2 + 4y + 4 = 4
    Hence, x^2 + y^2 - 6x + 4y + 9 = 0
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Equation of a circle in 3d
    Posted in the Geometry Forum
    Replies: 6
    Last Post: January 14th 2011, 01:17 PM
  2. Equation of a Circle
    Posted in the Geometry Forum
    Replies: 3
    Last Post: August 27th 2010, 08:44 PM
  3. Equation of a circle
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: November 14th 2009, 05:26 PM
  4. Equation for a circle.
    Posted in the Calculus Forum
    Replies: 3
    Last Post: August 11th 2008, 09:00 PM
  5. Equation of a Circle
    Posted in the Geometry Forum
    Replies: 8
    Last Post: August 6th 2008, 12:21 PM

Search Tags


/mathhelpforum @mathhelpforum