Simplify $(3x-8)+(5x+7)$.
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Simplify $(3x-8)+(5x+7)$.
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
8x -1
Simplify $(3x-8)+(5x+7)$.
train