A flat shape with 4 straight sides that:
• has two pairs of sides
• each pair of sides are adjacent (they meet) and equal in length.
Also the angles are equal where the pairs meet.
The dashed lines are diagonals, which meet at a right angle. And one of the diagonals bisects (cuts equally in half) the other.
Try moving the points below:
../geometry/images/geom-quad.js?mode=kite