若方程4xm-n-5ym+n﹦6是二元一次方程,则m﹦______,n﹦______.
根据题意,得
m-n=1m+n=1
解,得m=1,n=0.
—_____ are you?
—I'm fine.[ ]
A. How old
B. What
C. Is
D. How
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