
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
[asy] draw((0,0)--(0,4)--(5,0)--cycle,dot); draw((5,0)--(9,0)--(9,15)--cycle,dot); draw((0,4)--(9,15),dot); MP("C",(0,0),SW);MP("A",(0,4),NW);MP("B",(5,0),S);MP("E",(9,0),SE);MP("D",(9,15),NE); [/asy]
Triangle $ABC$ has a right angle at $C, AC=4$ and $BC=5$. Triangle $ABD$ has a right angle at $A$ and $AD=15$. Points $C$ and $D$ are on opposite sides of $\overline{AB}$. The line through $D$ parallel to $\overline{AC}$ meets $\overline{CB}$ extended at $E$. Calculate $\frac{DE}{DB}$.

Present the answer in LaTex format: \boxed{Your answer}
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