kite
A kite or deltoid is a quadrilateral with two pairs of equal sides, each pair consisting of adjacent sides
. Contrast with parallelograms
, where the equal sides are opposite.
The pairs of equal sides imply several properties:
- •
One diagonal
divides the kite into two isosceles triangles
, and the other divides the kite into two congruent triangles.
- •
The angles between the sides of unequal length are equal. In the picture, they are both equal to the sum of the blue angle with the red angle.
- •
The diagonals are perpendicular
.
- •
If and are the lengths of the diagonals, then the area is
Alternatively, if and are the lengths of the sides, and the angle between unequal sides, then the area is
- •
A kite possesses an inscribed circle. That is, there exists a circle that is tangent (touches) the four sides.
- •
Kites always possess at least one symmetry
axis, being the diagonal that divides it into two congruent triangle.
When all the side lengths are the same, the kite becomes a rhombus, and when both diagonals have the same length, the kite becomes a square.