| Construction Algorithm | ||
| 1 |  |
Construct a line AB as a given base of the parallelogram. |
| 2 |  |
Construct a point M above the line AB. |
| 3 |  |
Define a reflection at the point M, then construct the images of the two points A and B by reflection on M by selecting them to get the other two vertices of the parallelogram C and D. |
| 4 |  |
Join up the four points A, B, C and D to get the required parallelogram. |
| 5 |  |
Switch to drag mode. Pick a free element. Move it around to check your construction. |
| Construction Theorems | ||
| A parallelogram is a
quadrilateral, in which diagonals bisect each other. Reflection preserves the distance between points. |
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