If $x + y = 7$ and $x - y = 9$, find the product of $x$ and $y$.
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
If $x + y = 7$ and $x - y = 9$, find the product of $x$ and $y$.
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
-8
If $x + y = 7$ and $x - y = 9$, find the product of $x$ and $y$.
train