Exploring Special Lines of Reflection
Reflection of a quadrilateral across a line.
Notice that the lines extending from one point to its corresponding point are bisected by the line of reflection. This means that to reflect a point, line or object means to reconstruct it identical mirror image at exactly the same distance from the line/point of reflection.
Try moving the line of reflection by grabbing point E to see what happens.
Reflection over the Y-axis:
Put the line of reflection on the y-axis.
What are the coordinates of the preimage points A?
What are the coordinates of the image point A'?
What happens to a point that is reflected over the y-axis?
Reflection over the X-Axis
Put the line of reflection over the x-axis.
What are the coordinates of the preimage points A?
What are the coordinates of the image point A'?
What happens to a point that is reflected over the x-axis?
Reflection over the line Y=X
Put the line of reflection at the line y=x.
What are the coordinates of the preimage points A?
What are the coordinates of the image point A'?
What happens to a point that is reflected over the line y=x?
Reflection over the line Y=-X
Put the line of reflection at the line y=-x.
What are the coordinates of the preimage points A?
What are the coordinates of the image point A'?
What happens to a point that is reflected over the line y=-x?