Let D be an interior point of the triangle ABC .
CD and AB intersect at Dc ,
BD and AC intersect at Db ,
AD and BC intersect at Da .
Prove that there exists a triangle KLM with orthocenter H and the feet of altitudes Hk∈LM,Hl∈KM,Hm∈KL , so that
(ADcD)=(KHmH)(BDcD)=(LHmH)(BDaD)=(LHkH)(CDaD)=(MHkH)(CDbD)=(MHlH)(ADbD)=(KHlH)