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PROJECT EULER · #0257

Angular Bisectors

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Given is an integer sided triangle ABC with sides abc. (AB=c, BC=a and AC=b.)
The angular bisectors of the triangle intersect the sides at points E, F and G (see picture below).

0257_bisector.gif

The segments EF, EG and FG partition the triangle ABC into four smaller triangles: AEG, BFE, CGF and EFG.
It can be proven that for each of these four triangles the ratio area(ABC)/area(subtriangle) is rational.
However, there exist triangles for which some or all of these ratios are integral.

How many triangles ABC with perimeter 100000000 exist so that the ratio area(ABC)/area(AEG) is integral?

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