In the above figure, $AB = 12$, $FE = 8$, $BC = CD = DE = 3$, $AB\perp BE$, $FE\perp BE$,
Then find the area of $\Delta GCD$.
If we draw perpendicular GM to BE then we form two triangles
Triangle GMD is similar to triangle ABD ....and triangle FEC is similar to triangle GMC
So And
AB/ BD = GM / x FE / CE = GM/ 3 -x
12/6 = GM /x 8 / 6 = GM / 3 - x
2 = GM / x 4 / 3 = 2x / 3 - x cross- multiply
GM = 2x 4(3 -x) = 3 * 2x
12 - 4x = 6x
12 = 10x
x =12/10 = 6/5
So GM = 2 (6/5) = 12/5
So [ GCD ] = 1/2 ( CD) ( GM) = 1/2 ( 3) (12/5) = 36/10 = 3.6