You can
put this solution on YOUR website! .
Hint: Add the areas of two triangles.
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Your formulation contains a lot of unnecessary words.
Compare yours
A kite has a longer diagonal of "a" and a shorter diagonal of "b". Prove that the area of the kite is (a*b)/2
and my:
A kite has diagonals of "a" and "b". Prove that the area of the kite is (a*b)/2