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Discussion of Problem 1647. Divide an Island!

IgorKoval(from Pskov) Algo. [4] // Problem 1647. Divide an Island! 9 Apr 2012 02:25
What is algorithm? What formulas, theorems, equations and hints must I use?
IgorKoval(from Pskov) Re: Algo. [2] // Problem 1647. Divide an Island! 15 May 2012 22:53
Is here some adia? =)
2rf Re: Algo. [1] // Problem 1647. Divide an Island! 16 May 2012 03:07
Suppose that answer is XY, where point X lies on CA and Y lies on CB. Then let CX = x, CY = y. Now you have two equations: x + y = P/2, x * y = CA * CB / 2 (P is perimeter). The rest of solution is straightforward.
IgorKoval(from Pskov) Re: Algo. // Problem 1647. Divide an Island! 16 May 2012 23:59
Thank you very much! Very good adia!

P.S.:
How get x * y = CA * CB / 2  ?
Just simple:
2 * SQUARE_CXY == SQUARE_ABX
2 * 0.5 * x * y * sinXCY == 0.5 * CA * CB * sinXCY
x * y == 0.5 * CA * CB
x * y = CA * CB / 2
I think about it several minute. =)
tyomitch Re: Algo. // Problem 1647. Divide an Island! 12 Feb 2013 23:33
See http://mathcentral.uregina.ca/mp/previous2011/apr12sol.php for the detailed account of this problem (history, solutions, etc.)