
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
Given line l<sub>0</sub>: x - y + 1 = 0, line l<sub>1</sub>: ax - 2y + 1 = 0 is perpendicular to l<sub>0</sub>, and line l<sub>2</sub>: x + by + 3 = 0 is parallel to l<sub>0</sub>. Find the value of a + b.

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