Page 2 of 2 FirstFirst 12
Results 11 to 20 of 20

Thread: URGENT - Maths Help

  1. 27th July 2017, 07:49 PM #11
    weeds's Avatar
    weeds
    weeds is offline Swaggie
    Join Date
    Feb 2005
    Location
    Bracken Ridge - Brisbane - QLD
    Posts
    14,276
    Total Downloaded
    0
    Quote Originally Posted by NavyDiver View Post
    This is better if you dont wish to do the maths yourself

    Equilateral Triangle Equations Formulas Calculator - Inscribed Circle Radius GeometryInscribed Circle Radius (r)
    = 430.12595054627


    I think that for the radius of a circle inside a triangle...I need the radius for a circle on the outside of the triangle.
    Reply With Quote Reply With Quote
  2. 27th July 2017, 07:50 PM #12
    Homestar's Avatar
    Homestar
    Homestar is offline Super Moderator & CA manager Subscriber
    Join Date
    Aug 2010
    Location
    Sunbury, VIC
    Posts
    20,105
    Total Downloaded
    0
    Use this - Irregular Triangle Calculator

    Angles a and c will be 30 degrees (half of the 60 degrees that each corner of the equilateral triangle makes). Side b is your dimension of 1490.
    If you need to contact me please email homestarrunnerau@gmail.com - thanks - Gav.
    Reply With Quote Reply With Quote
  3. 27th July 2017, 07:54 PM #13
    Homestar's Avatar
    Homestar
    Homestar is offline Super Moderator & CA manager Subscriber
    Join Date
    Aug 2010
    Location
    Sunbury, VIC
    Posts
    20,105
    Total Downloaded
    0
    Here's a diagram.

    IMG_0539.jpg
    If you need to contact me please email homestarrunnerau@gmail.com - thanks - Gav.
    Reply With Quote Reply With Quote
  4. 27th July 2017, 07:55 PM #14
    cripesamighty's Avatar
    cripesamighty
    cripesamighty is offline ChatterBox Silver Subscriber
    Join Date
    Aug 2008
    Location
    Perth, WA
    Posts
    2,479
    Total Downloaded
    37.36 MB
    Try this link. Move the triangle around in the frame so each side is equal to 14.9 (as per your drawing). It then gives you a radius of 8.6, or diameter of 17.2. Hope that's close enough.

    Circumcircle of a Triangle - Math Open Reference


    Edit: Beat me to it. Looks like Homestar gets a Gold star!
    Reply With Quote Reply With Quote
  5. 27th July 2017, 07:57 PM #15
    weeds's Avatar
    weeds
    weeds is offline Swaggie
    Join Date
    Feb 2005
    Location
    Bracken Ridge - Brisbane - QLD
    Posts
    14,276
    Total Downloaded
    0
    Quote Originally Posted by weeds View Post
    I found this....but it's not making sense to me.

    An equilateral triangle of side 6cm is inscribed in a circle. How do I find the radius of the circle? - Quora
    OK......my grade 12 son said the formula is in this link...only problem is I couldn't figure out what root 3 meant...his calculator has it.
    Reply With Quote Reply With Quote
  6. 27th July 2017, 07:57 PM #16
    weeds's Avatar
    weeds
    weeds is offline Swaggie
    Join Date
    Feb 2005
    Location
    Bracken Ridge - Brisbane - QLD
    Posts
    14,276
    Total Downloaded
    0
    Quote Originally Posted by Homestar View Post
    Here's a diagram.

    IMG_0539.jpg
    Spot on.....

    Cheers
    Reply With Quote Reply With Quote
  7. 27th July 2017, 07:58 PM #17
    weeds's Avatar
    weeds
    weeds is offline Swaggie
    Join Date
    Feb 2005
    Location
    Bracken Ridge - Brisbane - QLD
    Posts
    14,276
    Total Downloaded
    0
    Cheers all.....bugger me
    Reply With Quote Reply With Quote
  8. 27th July 2017, 08:05 PM #18
    Homestar's Avatar
    Homestar
    Homestar is offline Super Moderator & CA manager Subscriber
    Join Date
    Aug 2010
    Location
    Sunbury, VIC
    Posts
    20,105
    Total Downloaded
    0
    I had to engage brain cells I'd not used for many decades...

    Pretty happy I haven't killed them all.... yet...
    If you need to contact me please email homestarrunnerau@gmail.com - thanks - Gav.
    Reply With Quote Reply With Quote
  9. 27th July 2017, 08:23 PM #19
    NavyDiver's Avatar
    NavyDiver
    NavyDiver is offline Very Very Lucky! Gold Subscriber
    Join Date
    Feb 2010
    Location
    Melbourne
    Posts
    10,247
    Total Downloaded
    0
    I just engaged Dr Google and as usual it missed
    Reply With Quote Reply With Quote
  10. 29th July 2017, 05:39 AM #20
    Piddler's Avatar
    Piddler
    Piddler is offline Master
    Join Date
    Jan 1970
    Location
    North West Tasmania
    Posts
    869
    Total Downloaded
    0
    Yes the trigonometry is correct, but as I tell my students if really stuck get some chalk and draw it life size on the ground.
    Alternatively draw in a CAD program on computer.

    Cheers
    Reply With Quote Reply With Quote
Page 2 of 2 FirstFirst 12
« Young Lady having a bad day | ACCC taking Ford to Court »

Tags for this Thread

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Forum Rules

Search AULRO.com ONLY!
 Search All the Web!