We learned about reflection and how you do them. A reflection is a mirrored image on the other side of the graph. The A is the preimage and A’ is the image. When the problem says reflect on the y-axis you have to multiply the x-coordinate by -1. You do the same when it say reflect of the x-axis but you have multiply the y-coordinate by -1. When it says reflect a point in the line y=x you have to switch the the x and y coordinates with each other. For example (x,y) to (y,x).
Alexis Andrews Geometry Blog 