July 5th, 2018, 12:18 AM  #1 
Senior Member Joined: Nov 2010 From: Indonesia Posts: 2,001 Thanks: 132 Math Focus: Trigonometry  [ASK] Two Cones
Azis wants to make two cones using cartons. The surface area of the first cone is twice the second. The side length of the first cone is also twice the second. Determine the ratio of those cones' radius! s1 = 2s2 L1 = 2L2 πr1(r1 + s1) = 2πr2(r2 + s2) r1(r1 + 2s2) = 2r2(r2 + s2) I was stuck with quadratic equations... 
July 5th, 2018, 02:41 AM  #2 
Senior Member Joined: Aug 2012 Posts: 2,157 Thanks: 631  
July 5th, 2018, 05:48 PM  #3 
Senior Member Joined: Nov 2010 From: Indonesia Posts: 2,001 Thanks: 132 Math Focus: Trigonometry  
July 5th, 2018, 10:59 PM  #4 
Global Moderator Joined: Dec 2006 Posts: 20,310 Thanks: 1980  
July 5th, 2018, 11:04 PM  #5 
Senior Member Joined: Nov 2010 From: Indonesia Posts: 2,001 Thanks: 132 Math Focus: Trigonometry  
July 6th, 2018, 01:15 AM  #6 
Global Moderator Joined: Dec 2006 Posts: 20,310 Thanks: 1980 
According to Google's translator, "luas permukaan" means "surface area" (as distinct from "total surface area"). Although a more specific phrase is available, it's possible that the need for it was overlooked.


Tags 
cones 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
sewing conundrum concerning cones  thewitchmaker  Geometry  1  January 28th, 2015 05:19 PM 
About Triangles in Cones  Correia  Algebra  2  July 14th, 2013 09:13 AM 
intersection of two cones  white_flag  Algebra  2  July 30th, 2012 07:46 AM 
equation of intersaction of two cones  PackElend  Algebra  0  May 8th, 2009 06:21 AM 
Polynomials and Cones  AdamL12  Abstract Algebra  9  November 15th, 2007 02:44 PM 