Similar Triangle

DC  is parallel to AB

And FG  = 3  and AB  = 6

Therefore.....FG splits the sides of triangle AEB  in a 1: 1 ratio

This also  means that the altitude of triangle EFG  = BC  = 3

So...the altitude of triangle AEB is twice this = 6

So...the area of triangle AEB  =  1/2 * AB *  2 BC =   1/2 * 6 * 6  =  18 units^2

Thank you so much Chris