Move the points in the grafic or define the point coordinates in the numeric field.
The opposite sides are the same. The opposite sides are parallel. The diagonals halve each other. Opposite angles are equal. Two adjacent angles together result 180 °.
With the side length a = AB = CD und b = BC = DA result the circumference:
With the side length a and b and the angle α is the area:
With the side lengths a and b the length of the diagonals is given by: