Which transformation involves flipping a shape?

The transformation that involves flipping a shape is reflection. In a reflection, a shape is mirrored over a line, called the line of reflection, resulting in a new shape that is a mirror image of the original. This means that every point of the original shape is mapped to a corresponding point on the other side of the line at an equal distance.

Reflection is distinct from other transformations such as rotation, which involves turning a shape around a fixed point, dilation, which changes the size of a shape while maintaining its proportions, and translation, which involves sliding a shape from one position to another without altering its orientation or size. Each of these other transformations affects the position or size of the shape but does not involve flipping it.