Assertion: parallelepiped's side | /r/HasProperty | given by vector
Facets:
Source sentences:
text: The statement that the area of a parallelogram with sides given by the vectors (a, b) and (c, d) is |ad - bc| is obviously true if b and c are 0, since the parallelogram is then a rectangle with sides |a| and |d|, whose area is |ad|.