In triangle $ABC$, points $D$ and $F$ are on $\overline{AB},$ and $E$ is on $\overline{AC}$ such that $\overline{DE}\parallel \overline{BC}$ and $\overline{EF}\parallel \overline{CD}$. If $AF = 9$ and $DF = 3$, then what is $BD$?
Have you drawn the picture?
If you have then you will see that there are 2 pairs of similar triangles.
You can solve the ratios simultaneously to get your answer. This part is actually very easy.
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