Results 1 to 3 of 3

Thread: ratio of circle to triangle

  1. #1
    rcs
    rcs is offline
    Senior Member rcs's Avatar
    Joined
    Jul 2010
    From
    iligan city. Philippines
    Posts
    486
    Thanks
    2

    ratio of circle to triangle

    A triangle is formed inside a circle by connecting the center C to two
    points A and B on the circle. If angle ACB = 30degrees, what is the ratio of the
    areas of the circle to the triangle?

    i want to find the area of the triangle but their is no measure of the sides so that i can find the area of the triangle. then area of a circle too
    please help me on this problem...
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    12,880
    Thanks
    1946
    Call the radius $\displaystyle \displaystyle r$. The triangle will be isosceles and the two equal sides will be this length.

    Area of circle: $\displaystyle \displaystyle \pi r^2$.

    Area of triangle: $\displaystyle \displaystyle \frac{1}{2}\cdot r \cdot r \cdot \sin{30^{\circ}} = \frac{1}{2}\cdot r^2 \cdot \frac{1}{2} = \frac{1}{4}r^2$.


    So the ratio of circle's area to triangle's area is $\displaystyle \displaystyle \frac{\pi r^2}{\frac{1}{4}r^2} = 4\pi$.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    rcs
    rcs is offline
    Senior Member rcs's Avatar
    Joined
    Jul 2010
    From
    iligan city. Philippines
    Posts
    486
    Thanks
    2
    Prove it ... thank u so so much... Your are one of the Bests in MHF
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Triangle Ratio Problem (I think)
    Posted in the Geometry Forum
    Replies: 4
    Last Post: May 4th 2011, 06:32 PM
  2. Replies: 2
    Last Post: Feb 6th 2010, 08:31 AM
  3. Replies: 27
    Last Post: Apr 27th 2008, 10:36 AM
  4. Ratio of a Triangle
    Posted in the Geometry Forum
    Replies: 3
    Last Post: Mar 16th 2008, 10:28 AM
  5. triangle ratio
    Posted in the Geometry Forum
    Replies: 3
    Last Post: Dec 10th 2006, 01:52 PM

Search Tags


/mathhelpforum @mathhelpforum