
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 $\overrightarrow {e_{1}} = (2, 1)$, $\overrightarrow {e_{2}} = (1, 3)$, $\overrightarrow {a} = (-1, 2)$, if $\overrightarrow {a} = \lambda_1 \overrightarrow {e_{1}} + \lambda_2 \overrightarrow {e_{2}}$, then the pair of real numbers $(\lambda_1, \lambda_2)$ is \_\_\_\_\_\_.

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