Respuesta :

B

6/4=18/X
6x= 72
X=12

Or you can say 4+4+4=12
GEF~CBF, because <F is general and <GEF=<CBF=90°. => GE:CB=EF:BF=6:18=1:3
GE:CB=1:3
4:CB=1:3
CB=12
The answer is B