area of kite is equal to 1/2 the product of the lengths of the diagonals
so
A=1/2(AD)(BF)
BF=BG+GF=8+8=18
AD=AG+GD=7+13.5=20.5
A=1/2(20.5)(18)=(8)(20.5)=164
now minus the area of the square
area of square=side^2=(CE)^2=9^2=81
kite-square=164-81=83 square meters
