Try this Drag the orange dots on each
vertex
to reshape the kite. The area is continuously recalculated.
Two methods for calculating the area of a kite are shown below. Choose a formula or method based on the values you know to begin with.
1. The "diagonals" method
If you know the lengths of the two diagonals, the area is half the product of the diagonals.
This is the method used in the figure above. As a formula:

where
d_{1} is the length of a diagonal
d_{2} is the length of the other diagonal


This also works for finding the
area of a rhombus, and the
area of a square since a
rhombus
is a particular kind of kite (one where all four sides are congruent) and a
square
is a particular kind of rhombus (where all angles are 90°).
2. Using trigonometry
If you know the length of two unequal sides and their
included angle,
this formula can be used, but requires a knowledge of trigonometry (see
Trigonometry Overview).

where
a,b are the lengths of two unequal sides
C is the angle between them
sin is the sine function (see Trigonometry Overview)


Other polygon topics
General
Types of polygon
Area of various polygon types
Perimeter of various polygon types
Angles associated with polygons
Named polygons
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