
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
In the same Cartesian coordinate system, the line $y_{1}=3x+1$ intersects the $x$-axis and $y$-axis at points $A$ and $B$ respectively, and the line $y_{2}=kx+b$ intersects the $x$-axis and $y$-axis at points $C$ and $D$ respectively. If $AB$ is parallel to $CD$, point $D$ is below point $B$, and $BD=6$, then the expression of the line $y_{2}$ is ______.

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