"midsegment" is referenced in the pages listed below.
This page shows how to construct (draw) the midsegment of a triangle with compass and straightedge or ruler. The midsegment of a triangle is a line which links the midpoints of two sides of the triangle. A Euclidean construction.
Trapezoid median (midline or midsegment) definition and properties
Definition and properties of the midsegment of a triangle
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