4.1 Reflection "Rules"
A reflection is a transformation that uses a line like a mirror to reflect or "flip" a figure. The mirror line is called the "line of reflection."
The following activities will help you explore various types of reflections. Like the last exploration, observe how this type of transformation affects the points, segments and angle measures of the figure when creating the image.
Reflection over the y-axis (x = 0)
Reflection over the x-axis (y = 0)
Reflection over the line y = x
Reflection over the line y = -x
Reflection over the y-axis: Do you notice a pattern for how the coordinates change? What is it?
Reflection over the x-axis: Do you notice a pattern for how the coordinates change? What is it?
Reflection over the line y=x: Do you notice a pattern for how the coordinates change? What is it?
Reflection over the line y=-x: Do you notice a pattern for how the coordinates change? What is it?
How do reflections impact the length of segments or angle measures?