Open Middle®
Directions: What is the fewest number of transformations needed to take pre-image ABCD to image A’B’C’D’?
Hint
What transformations do you need to use? Can you use the same transformations and do it another way?
Answer
A single reflection across a line that is roughly parallel to line segment DA in the pre-image will do it in one move. Otherwise students will likely get it in 2 moves by using a rotation and a reflection.
Source: Robert Kaplinsky
A reflection that takes A to A’ can only be in the perpendicular bisector of AA’
Same goes for B and B’ and these two lines are not the same. So no single reflection.
Maybe they put in the wrong diagram?
It means take ABCD to A’B’C’D’ up to translation; the actual location of the shapes is meant to be irrelevant here.
Yes, Ben is correct.
I should state that the actual location is irrelevant then. Not stating that would create major confusion.
Reflection between the middle of the pre-image and image, and rotate 180degree at the middle point.
Its kind of unclear what its asking, but if it means orientation then reflect across line AD
2 transformations. Reflection and a rotation.
You could rotate the pre imagine until it looks like a mirror image of shape A’B’C’D’, then a reflection between the two images.
A reflection across the middle of the two shapes that’s vertical and then a rotation 90 degrees clockwise