Investigating Reflections

Triangle ABC is relected about the blue line. Move the blue line, by using the blue point on the line, and move Points A,B, and C to investigate how the original points' coordinates and the images of the points' coordinates relate to each other. Use the worksheet to answer the questions below.
1. Move the blue point so the line is x=0 (y-axis). 2. Make a conjecture about what you think the coordinates of the vertices of the image will be after you reflect the triangle over the y-axis. 3. Click the box Show Reflection. 4. What do you notice about the coordinates A', B', and C' in relation to the original points. 5. Move the points A, B, and C. What do you notice about the image points? 6. Click Show AA', Show BB', and/or Show CC'. 7. What do you notice about the segment that connects the original point and the image point? Repeat steps 1-7 for the x-axis, the line y=x, and the line y=-x.