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?

translate by ()

To determine the next step, we need to consider that rotating a shape does not change its size or shape, only its orientation. So, if the first rectangle is congruent to the rectangle in Quadrant I after rotating it 90 degrees clockwise, the next step would be to translate the rotated rectangle to match the position of the rectangle in Quadrant I.

However, the translation amount is missing from the given question ("translate by ()"). We would need to know the exact values for translation to complete the process of determining the congruence.