Exploring Reflections with GeoGebra

Reflecting in GeoGebra

Use the tool that looks like a division symbol to reflect.[br]When using this tool, click on the object you want to reflect, then the line of reflection.[br]Reflect the following across reflection line QR[br] -Point M[br] -Line AB[br] -Triangle TOP[br]After performing these reflections change to the select tool to move the objects and/or the reflection line to investigate properties of a reflection.

Properties of a Reflection

Which of the following properties apply to all reflections? (Choose all that apply)[br]Record your answers in the Properties section of the Rigid Transformations Worksheet.

Orientation is preserved. This means order of points around the pre-image polygon are in the same direction as the image. (In general if TOP is clockwise, so is T'O'P') Segments formed by pre-image and matching image are parallel. (In general segment AA' // segment BB') Distances between pre-image and matching images are equal. (In general AA'=BB') The line of reflection is the perpendicular bisector of the segments between each pre-image and image point. (In general QR is perpendicular bisector of segment AA') Distance is preserved. This means lengths between pre-image points are the same as lengths between their images. (In general AB = A'B') Angle measure is preserved. This means angle measures between pre-image points are the same measure as the angles between their images. (In general angle TOP = angle T'O'P')

Exploring Reflections with GeoGebra

Reflecting in GeoGebra

Properties of a Reflection

Information: Exploring Reflections with GeoGebra