[] , [] , [^] , []Area of a triangle of which three points are each foot of perpendicular / Confirming with measurement (Minimum)(GC World : Various Problems ,MaxEMin)
There are ABC and point P.
Perpendicular feet drawn from point P to three sides are named D, E, and F respectively.
If point P moves, when will the area of DEF be 0?


Forum of Geometric Constructor by Y.Iijima