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July 29th, 2012, 09:27 AM   #1
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Split area

An "all integer" example: isosceles triangle; AB = AC = 442 ; BC = 84.
D is on AB, 104 from B; E is on AC, 153 from C.
Line DE = 77.
Triangle ADE's area = half of triangle ABC's area.
Code:
           A

            289

     338
               E
          77
    D
                 153
 104

B         84         C
As general case: given is AB (or AC), BC and BD; make 'em : AB=AC=a, BC = b and BD = d

Calculate DE in terms of a,b,d

Just for something to do
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July 31st, 2012, 12:01 PM   #2
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Re: Split area

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July 31st, 2012, 12:18 PM   #3
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Re: Split area

Looksee good! Mine:

AD = f = a - d (given)
angleBAC = u = 2ASIN[b/(2a)] (given)

CE = e = [4afSIN(u) - bSQRT(4a^2 - b^2)] / [4fSIN(u)]

DE = SQRT[(a - e)^2 + f^2 - 2f(a - e)COS(u)]
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