Have the ever looked in a river or pool and seen your reflection off of the water? In geometry, reflections are very similar to that. When a geometric shape or figure undergoes a flip movement it is called a reflection. To be a true reflection every point of the figure change has to be the same size and same distance from the central line between the figure and the reflection. In space exploration reflective devices power many of the communication device on shuttles. Being able to identify this is not an easy skill and students that have a poor sense of depth perception often struggle with the concept. The thing I find these students lack or maybe even skip over is the fact that a mirror image does not have to always be horizontal (meaning left to right), they can go in any direction on a pivot point. The best way to identify these movements is to focus on each corner of the shapes and draw a mirror line to the points of the suspected reflected object. If it is a true mirror line the points will hit the mirror line at a ninety-degree angle for each point. Then just play connect the dots from there.
These worksheets look at a reflection made over an axis. It really helps if you draw these out, some will already be drawn for you. To determine if a true reflection occurs make sure that the point is an equidistance for the mirror of center line. You will also need to take the time to position your point near the mid-line of the axis. This really helps you visualize the movement of the point across the coordinate.