<span><span>Reflection in a Line <span>Topic Index | Geometry Index | Regents Exam Prep Center</span></span> <span><span> </span><span>A </span>reflection<span> over a line k (notation </span><span>rk</span><span>) is a transformation in which each point of the original figure (pre-image) has an image that is the same distance from the line of reflection as the original point but is on the opposite side of the line. Remember that a reflection is a flip. Under a reflection, the figure does not change size.
</span> The line of reflection is the perpendicular bisector of the segment joining every point and its image.</span> <span>A line reflection creates a figure that is congruent to the original figure and is called an isometry (a transformation that preserves length). Since naming (lettering) the figure in a reflection requires changing the order of the letters (such as from clockwise to counterclockwise), a reflection is more specifically called a non-direct or <span>opposite isometry.
