solution: Distribute the factor of 6 and simplify to obtain $(1+2i)6-3i=6+12i-3i=\boxed{6+9i}$.
prompt.content: <|im_start|>system
  You are a helpful assistant.<|im_end|>
  <|im_start|>user
  Evaluate $(1+2i)6-3i$.
  Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
  <|im_start|>assistant
  
prompt.role: user
extra_info.answer: 6+9i
extra_info.question: Evaluate $(1+2i)6-3i$.
extra_info.split: test