Question

Theorem: A line parallel to one side of a triangle divides the other two proportionately.

Answer 1

 Segment BF = 18
just took the test

Answer 2

In your question which ask for the statement that best fit in your theorem that a parallel line to one side of a triangle divides the other two porportionately which states that segment DE is parallel to segment BC and segment EF is parallel to AB so the answer is BD=15