Results 1 to 2 of 2

Math Help - Lengths of triangle

  1. #1
    Junior Member
    Joined
    Feb 2007
    From
    NEW YORK
    Posts
    63

    Lengths of triangle

    Two triangles are similar. The lengths of the sides of the smaller triangle are 3, 5, and 6, and the lengths of the longest side of the larger triangle is 18. What is the perimeter of the larger triangle.

    1) 14
    2) 18
    3) 24
    4) 42

    Explain.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    is up to his old tricks again! Jhevon's Avatar
    Joined
    Feb 2007
    From
    New York, USA
    Posts
    11,663
    Thanks
    3
    Quote Originally Posted by aznmartinjai View Post
    Two triangles are similar. The lengths of the sides of the smaller triangle are 3, 5, and 6, and the lengths of the longest side of the larger triangle is 18. What is the perimeter of the larger triangle.

    1) 14
    2) 18
    3) 24
    4) 42

    Explain.
    since the two triangles are similar, the lengths of their sides are proportional. the longest side of the small triangle is 6, and the longest side of the large triangle is 18

    note that 18 = 3*6, so the larger triangle is larger than the small triangle by a factor of 3, it means that the lengths of the other sides of the larger triangle are 3*3 = 9 and 3*5 = 15

    so all the sides of the large triangle are 9, 15 and 18, use these to find the perimeter
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Triangle side lengths
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: April 2nd 2011, 06:56 AM
  2. Replies: 3
    Last Post: May 23rd 2010, 02:26 AM
  3. Lengths in a Triangle
    Posted in the Geometry Forum
    Replies: 1
    Last Post: May 14th 2009, 06:25 PM
  4. Finding Missing Triangle Lengths...
    Posted in the Trigonometry Forum
    Replies: 36
    Last Post: April 1st 2008, 11:01 AM
  5. Area of triangle with side lengths 8, 10, 12
    Posted in the Geometry Forum
    Replies: 1
    Last Post: January 25th 2006, 10:16 PM

Search Tags


/mathhelpforum @mathhelpforum