Online Geometry
Problem 472. Triangle, Parallel, Side, Parallelogram,
Area, Similarity
The figure shows a triangle ABC of
area S. Lines DE, FG, and HM are parallel to AC, BC, and AB
respectively. If S1, S2, S3,
and S4 are the areas of triangles DFN, PME, HGQ, and
NPQ respectively, prove that
.