| Construction Algorithm |
| 1 |
 |
Construct
a line AB as a given base of the parallelogram. |
| 2 |
 |
Construct
a point C above the line AB and the line passing through it parallels
AB. |
| 3 |
|
Construct
a line joining between B and C. |
| 4 |
|
Construct
a line parallel to BC through point A. |
| 5 |
 |
Generate
the intersection points between the two lines to find the fourth vertex
D of the parallelogram. |
| 6 |
 |
Join up the four points A, B, C and D to get the required parallelogram. |
| 7 |
 |
Switch
to
drag mode. Pick
a free element. Move it around to check your construction. |
| Construction Theorem |
| A parallelogram is a
quadrilateral, in which each two opposite sides are parallel. |