Answer:
since E is between D and F ,
therefore we can say that ,
[tex] 3x - 1 + 13 = 6x \\ \\ 3x + 12 = 6x \\ \\ 6x - 3x = 12 \\ \\ 3x = 12 \\ \\ dividing \: both \: sides \: by \: 3 \\ \\ \frac{\cancel{3}x}{\cancel{3}} = \cancel{\frac{12}{3} } \\ \\ \longrightarrow \: \boxed{x = 4}[/tex]
hope it helps.
