Area of Kite

You have to learn the triangle and the area of ​​the triangle. Isosceles triangles have special properties. Two isosceles triangles are the same length of its base can be compiled into a wake kites. Kites are rectangular. The kite has two pairs of sides of equal length. Kite is formed of two isosceles triangles. Both triangles have the same base length, but different height.  

Area of ​​kite can also be found using the formula area of ​​the triangle. By calculating the area of ​​the isosceles triangles that make up the kite. After that, the results are summed. Area of ​​kite ABCD can be found by summing the area ΔADC with ΔABC.

• Area  ΔADC =  ½ x  AC x OD

                                           = ½ x  8 x 4
                                           = 4 x 4
                                           = 16 area unit

• Area  ΔABC =  ½ x  AC x OB

                                           =  ½ x 8 x 9

                                           = 4 x 9

                                           = 36 area unit

• Area  ΔABC  = 16 + 36

                                = 52 area unit

Area ABCD = Area ΔADC + Area  ΔABC
                     = ½ x  AC x OD + ½ x  AC x OB
                            = ½ x AC ( OD + OB)
                            = ½ AC x BD 
                            = ½ x d1 x d2

 d1 and d2 is the diagonal of the kite. From the area of kite kite above, can be determined the diagonals.

• d1  = 2A/d2
• d2 = 2A/d1

Example :

1. A kite has d2 = 15 cm and area = 150 cm

     d1 = 2x150/15

           = 300/15

           = 20 cm

2.  A kite has d1 = 20 cm and area = 250 cm

      d2 = 2x 250/20

            = 500/20

            = 25 cm

3.  John want to make a kite. Two pieces of bamboo are made John with 48 cm and 44 cm 

      long.  If the kite has made, how area of the kite ?

      Area = ½ x d1 x d2

                 = ½ x 48 x 44

                 = 24 x 44

                 = 1.056 cm

4. On the wall there is a kite-shaped image. Area of the picture = 5.400 cm² and one of the 
    diagonal length is 120 cm. How long is the other diagonal ?
    d2 = 2A/d1
          = 2 x 5.400/120
          = 10.800/120
          = 90 cm