What notation is used to represent reflections in transformation geometry?

The notation used to represent reflections in transformation geometry is "r." This notation signifies a reflection transformation, where a geometric figure is flipped over a line, known as the line of reflection. The use of "r" helps to distinguish this type of transformation from others, such as translations and dilations, which are symbolized by different letters.

This differentiation is vital in geometry, as each type of transformation—whether it is a rotation, translation, or dilation—has specific properties and effects on the figures involved. By using "r" for reflections, mathematicians and students can clearly communicate about the nature of the transformation being applied, ensuring clarity in discussions and solutions related to geometric problems.