Can you find the quadrilateral formed by the lines a x b y c = 0, a dash x b = 0, x b y c = 0, and a dash x b dash y c = 0? If the diagonals of this quadrilateral are perpendicular, what can you conclude about these lines? a. The quadrilateral is a rectangle b. The quadrilateral is a rhombus c. The quadrilateral is a square d. The quadrilateral is a parallelogram