Translations, Rotations, and Reflections

A translation (slide) moves every point of the plane in a specific direction along a straight line.  You are sliding the figure across a plane.  A great way to remember translation is that the "sl" in the word translation stands for slide!

Here are a couple of examples of translations:

A rotation is when you turn a figure about a fixed point (the center) a certain amount in a certain direction.  A way to remember that rotation is a turn by thinking of one of the t's in rotation stands for turn.

Here are a couple examples of rotations:

For the pentagon shown above, the figure was rotated clockwise at 90 degrees.

The Seahorse in the picture above was also turned clockwise at 90 degrees.  Even though the seahorse is an animal and not a "shape", it still gives a fun example of how to rotate a figure!

A reflection is a mirror image.  If you draw a line of reflection next to the image, the mirror image is presented on the other side of that line. A reflection reverses the orientation of the original figure.  A way to remember that reflection is a flip is by thinking that the "fl" in reflection stands for flip.

Here are a couple examples of reflections:

In the figure above, the line of reflection is the x-axis.  The first triangle is the one above the x-axis. It's reflection is pictured below the x-axis.  I can tell that this one is the reflection because they are marked with an apostrophe (A', B', C').  The apostrophe lets me know that this image is a reflection of the original image.

The next figure below is a much simpler example of a reflection.  It represents the fact that a reflection reverses the orientation of the original figure.  

The dotted line represents the line of reflection.  The letter "R" on the left is the original figure, while the "R" on the right is the reflection.