Difficult Geometry

[Chuck.b]

I need help with this problem. Ok suspect that the easiest method here is the one of "similar figueres" (triangels), but how ?

http://i.imagehost.org/0569/namnl_s.jpg

 

[Denis]

Chuck Berry?

Are you sure AC = 18? Not 16?

Let x = BD; then AD = 12 - x : OK?
And since AF = AD then AF = 12 - x; so CF = 18 - (12 - x) = x + 6 ; got that?

Carry on...

 

[Chuck.b]

Thanks man