In the figure below, prove that the
area S_{1} of the
central triangle region DFH determined by trisection of each
side of a triangle ABC and connecting the corresponding points
A', A", B', B", C', and C" with the opposite vertex is given by
1/25 the area of triangle ABC.
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FACTS AND HINTS:
Geometry problem solving is one of the most challenging skills for students to learn. When a
problem requires auxiliary construction, the difficulty of the problem increases drastically, perhaps because deciding which construction to make is an illstructured problem. By “construction,” we mean adding geometric figures (points, lines, planes) to a problem figure that wasn’t mentioned as "given."
