| Construction Algorithm |
| 1 |
 |
Construct
a line AC as a given diagonal of the square. |
| 2 |
 |
Construct
M as a midpoint of the diagonal AC. |
| 3 |
 |
Construct
the perpendicular line at M. |
| 4 |
 |
Construct
a circle centered at M and has a radius MC. |
| 5 |
 |
Generate
the intersection points between the circle and the perpendicular line
at M to construct B and D. |
| 6 |
 |
Join up the
four points A, B, C and D to get the required square. |
| 7 |
 |
Switch to
Move Mode. Pick a free element. Move it around to check your
construction. |
| Construction Theorem |
| The two diagonals of the
square are perpendicular to each other and equal in length. |