Answer:
12
Step-by-step explanation:
Fill in the given numbers and solve for BE.
... FD/EF = CD/BE
... 12/9 = 16/BE . . . . . the given numbers
... 12·BE = 9·16 . . . . . multiply by 9·BE ("cross multiply")
... BE = 144/12 = 12 . . divide by 12
