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PrintSecond Round, March 2019
Netherlands 2019 geometry
Problem
In a square of side length we draw lines from each vertex to the midpoints of the two opposite sides. For example, we connect to the midpoint of and to the midpoint of . The eight resulting lines together bound an octagon inside the square (see figure). What is the area of this octagon?

Solution
Final answer
2/3
Techniques
Cartesian coordinatesConstructions and loci