Category
page 1Lines defined for a triangle
median
median of a triangle
Euler line
straight line connecting multiple points that can be defined as the center of a triangle, such as the orthocenter, the circumcenter and the centroid
altitude
line segment in a triangle
Simson line
line defined from a triangle and a point on its circumcircle, through the closest point on each side line to the given point
cevian
In geometry, a cevian is a line segment which joins a vertex of a triangle to a point on the opposite side of the triangle. Medians, symmedians, angle bisectors, altitudes are all special cases of cevians. The name cevian comes from the Italian mathematician Giovanni Ceva, who proved a theorem about cevians which also bears his name.
symmedian
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central line
line associated with a triangle centre
cleaver
geometric term
Splitter
line segment through vertice of a triangle that bisects its perimeter