Is the other "vertical" line actually vertical, or is it "slanty" as well? What letters indicate the intersections of these lines with the original three lines? Do these "vertical" lines relate at all to the points A, B, C, D, E, and F? Are A, C, and E all on the same ends (say, the left-hand end) of the original three lines?
There needs to be additional information. Otherwise, with only what is posted so far, it is fairly simple to draw a picture in which DF is most definitely not
congruent to DE.