Let $x=\frac{7}{8}$ and $y=-\frac{2}{9}$.  If $x\cdot z = y$, then what is $z$?
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Let $x=\frac{7}{8}$ and $y=-\frac{2}{9}$.  If $x\cdot z = y$, then what is $z$?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
-\frac{16}{63}
Let $x=\frac{7}{8}$ and $y=-\frac{2}{9}$.  If $x\cdot z = y$, then what is $z$?
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