Results 1 to 2 of 2

Thread: [SOLVED] Geometry HELP!!! Triangular Pyramid

  1. #1

    [SOLVED] Geometry HELP!!! Triangular Pyramid


    I have a questions that I can't seem to answer, and I'm sure its pretty simple...I am very weak in Math, and I'm learning this on my own (homeschool). So here it is:

    I have to include the proper units ex. cm, in, m, etc....and I have to show all work!

    1. Find the lateral area of a regular triangular pyramid with base edge 3 in and slant height 4 in.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member wingless's Avatar
    Dec 2007
    This image demonstrates what base edge and slant height are.

    Look at the lateral triangle that slant height is drawn. Its base is 3 inches, like other base edges. All base edges are equivalent since it's a regular triangular pyramid.

    And we know that slant height is 4 inches. Aha! It's so easy, we have the base and the height of one of the lateral triangles. Its area is $\displaystyle 4x3/2 = 6$ square inches.

    If the area of one lateral triangle is 6 square inches, and there are 3 of them, what can the total lateral area be? As you see, there are 3 equivalent lateral triangles, each of them being 6 square inches. Then the total area is $\displaystyle 6x3 = 18$ square inches
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. triangular pyramid
    Posted in the Pre-Calculus Forum
    Replies: 1
    Last Post: Jun 10th 2011, 09:51 AM
  2. Replies: 1
    Last Post: Feb 24th 2011, 01:46 PM
  3. Area of a triangular pyramid
    Posted in the Geometry Forum
    Replies: 2
    Last Post: Apr 18th 2010, 12:58 PM
  4. problem with triangular geometry
    Posted in the Geometry Forum
    Replies: 3
    Last Post: Nov 29th 2009, 02:30 PM
  5. [SOLVED] Number pyramid
    Posted in the Algebra Forum
    Replies: 13
    Last Post: Feb 4th 2009, 10:50 AM

Search Tags

/mathhelpforum @mathhelpforum