Concurrentlines
A set of lines or curves are said to be concurrent if they all
intersect.
at the same point. In the figure below, the three lines are concurrent because they all intersect at a single point P.
The point P is called the "point of concurrency". This concept appears in the various centers of a triangle.
See Centers of a triangle.
Because lines extend indefinitely in both directions, unless they are
parallel
they will intersect somewhere.
Therefore, all nonparallel lines are concurrent.
Rays
and
line segments
may, or may not be concurrent, even when not parallel.
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