Area and perimeter of a parallelogram
- A parallelepiped is a quadrangle the opposite edges of which are parallel and the same length; the adjacent sides do not form a right angle.
- The diagonals are not the same length and perpendicular, but they halve one another.
- The heights are the perpendicular distances between the opposite edges.
parallelogram
| a, b | edge |
| d1,2 | diagonals |
| ha | height to edge a |
| hb | height to edge b |
| α1,2 | angle |