what transformation maps the preimage (red) onto the image (blue)?

Answer:
Rotate counter clockwise about the center point 180 degrees
Step-by-step explanation:
You can use transformations to preserve shape and size but move a shape or change its position. Transformations include:
To map the red into the blue, you can rotate it counter clockwise about the center point which the red and blue shapes share 180 degrees. It will land exactly on the red.