Projection of a Point onto a Line
Definition:
The projection of a point onto a line is the foot of the perpendicular segment drawn from the point to the line.
In the diagram, is the projection of onto line and is the projection of onto line .
Similarly, we can talk about the projection of an entire segment onto a line, which is just the segment joining the projections of the endpoints of the original segment. In the diagram, is the projection of onto line .
Drag and around to see how their projections move along line .