solution: Rearranging and grouping, we obtain $(19x - 4x) + (1 - 81) = \boxed{15x - 80}$.
prompt.content: <|im_start|>system
  You are a helpful assistant.<|im_end|>
  <|im_start|>user
  Simplify the following expression in $x$: $$19x + 1 - 4x - 81.$$
  Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
  <|im_start|>assistant
  
prompt.role: user
extra_info.answer: 15x - 80
extra_info.question: Simplify the following expression in $x$: $$19x + 1 - 4x - 81.$$
extra_info.split: test