The first step to determine that the rectangle in Quadrant III is congruent to the rectangle in Quadrant I was to rotate the first rectangle 90 degrees clockwise about the origin. What is the next step?
What is it translated by?
The next step is to reflect the rotated rectangle across the x-axis.
This reflection will result in the rectangle being translated by a certain distance. In this case, it will be translated by the length of the rectangle (or twice the distance from the origin to one of the rectangle's sides). The exact distance will depend on the size and location of the original rectangle.