To determine the coordinates of point B' after the translation of square ABDC, we need to know the original coordinates of point B.
Let's assume the coordinates of point B are (x, y). When the square is translated 2 units to the left, we subtract 2 from the x-coordinate, and when it is translated 4 units down, we subtract 4 from the y-coordinate.
So the new coordinates of point B' after translation will be:
B' = (x - 2, y - 4)
Please provide the original coordinates of point B if you want a specific numerical answer.