9514 1404 393
Answer:
E) 20
Step-by-step explanation:
The triangles are all similar, so the ratios of short to long sides are ...
EF/FC = CF/FD
8/CF = CF/50 . . . . . . use given values
400 = CF² . . . . . . . . . cross multiply
20 = CF . . . . . . . . . . . take the square root
