Why Not B - If we take the definition of a rhombus as, "A rhombus is a square with a lean. All sides have equal length, and opposite sides are parallel. Also, opposite angles are equal," then given the length of the diagonal "48" we should be able to find a side of the rhombus. My calculations show that the side is equal to 24 sqrt 2. Perimeter equals 24 sqrt 2 * 4.