Results 1 to 3 of 3

Math Help - triangle and ratios

  1. #1
    Senior Member sfspitfire23's Avatar
    Joined
    Oct 2009
    Posts
    273

    triangle and ratios

    Given a triangle ABC and a point 'D' divides the side AB such that a triangle ADC is formed & AD/DB=1/3. If the area of the triangle ABC is r, then find the area of the triangle ADC in terms of r?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    skeeter's Avatar
    Joined
    Jun 2008
    From
    North Texas
    Posts
    12,129
    Thanks
    1010
    let AB = b be the base of triangle ABC and h = height from C to AB ...

    area of triangle ABC = (1/2)bh = r

    since AD = (1/4)b

    area of triangle ADC = (1/2)(1/4)bh = (1/4)(1/2)bh = (1/4)r
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie Goethe's Avatar
    Joined
    Aug 2010
    From
    Washington
    Posts
    2
    AD/DB=1/3, so think of line AB as being divided into 4 equal segments, and that each of the three points dividing the line segments on AB have a straight line connecting to point C, creating 4 equal triangles within the triangle ABC, ADC being one of those

    therefore, triangle ADC=(1/4)r
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Triangle Ratios
    Posted in the Geometry Forum
    Replies: 1
    Last Post: November 11th 2009, 07:25 AM
  2. Ratios of line segments in a triangle
    Posted in the Geometry Forum
    Replies: 0
    Last Post: March 22nd 2009, 04:01 PM
  3. [SOLVED] Triangle ratios?
    Posted in the Geometry Forum
    Replies: 2
    Last Post: February 2nd 2009, 02:00 PM
  4. Ratios in a triangle
    Posted in the Geometry Forum
    Replies: 0
    Last Post: May 5th 2008, 01:50 AM
  5. Triangle ratios
    Posted in the Trigonometry Forum
    Replies: 0
    Last Post: November 21st 2006, 08:09 AM

Search Tags


/mathhelpforum @mathhelpforum