-Which describes the compositions of 3 reflections in three distinct lines, two of which are parallel?
1. rotation
2. dilation
3. translation
4. glide reflection
4. glide reflection
The correct answer is "4. glide reflection."
To determine which option describes the compositions of three reflections in three distinct lines, two of which are parallel, we need to analyze the characteristics of each transformation.
1. Rotation: A rotation is a transformation that turns an object around a fixed point. It does not involve reflection, so it is not the correct option for this scenario.
2. Dilation: A dilation is a transformation that changes the size of an object without altering its shape. It also does not involve reflection, so it is not the correct option.
3. Translation: A translation is a transformation that slides an object in a certain direction without changing its shape or orientation. Again, it does not involve reflection, so it is not the correct option.
4. Glide Reflection: A glide reflection is a combination of a translation and a reflection. It involves reflecting the object over a line, parallel to the two other lines mentioned, and then translating it along the reflection line. In this case, since two of the lines are parallel, the glide reflection is the correct option.
Therefore, the correct answer is option 4, glide reflection.