If $x$, $y$, and $z$ are real numbers for which  \begin{align*}
x+y-z &= -8, \\
x-y+z &= 18,\text{ and} \\
-x+y+z &= 30, \\
\end{align*} then what is $xyz$?
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
If $x$, $y$, and $z$ are real numbers for which  \begin{align*}
x+y-z &= -8, \\
x-y+z &= 18,\text{ and} \\
-x+y+z &= 30, \\
\end{align*} then what is $xyz$?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
1320
If $x$, $y$, and $z$ are real numbers for which  \begin{align*}
x+y-z &= -8, \\
x-y+z &= 18,\text{ and} \\
-x+y+z &= 30, \\
\end{align*} then what is $xyz$?
train