The first step to determine that the rectangular and quadrant III is congruent to the rectangle and quadrant one was to rotate the first rectangle 90 degrees clockwise without the organ what is the next steps
The next step would be to match the corresponding sides and angles of the two rectangles in order to show their congruence. This can be done by shifting the second rectangle, i.e., the one obtained after the clockwise rotation, without changing its orientation, such that its sides and angles align with those of the first rectangle (without overlapping them).
Once the two rectangles are aligned, you can compare the lengths of their corresponding sides and the measures of their corresponding angles to verify if they are equal. If all corresponding sides and angles are equal, you can conclude that the rectangular and quadrant III is congruent to the rectangle and quadrant one.