Answer:
The quadrilateral that can be formed is a parallelogram.
The reason for this is that the two legs of the ironing board, being of equal length and crossing over each other, create two pairs of congruent adjacent sides. In a quadrilateral, if opposite sides are parallel and congruent, it is a parallelogram. Since the two pairs of adjacent sides of the quadrilateral formed by the ironing board are parallel and congruent, it must be a parallelogram.