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2021 AMC 10D Question 12

AMC10 · 2021 AMC 10D

Question 12

Which of the following conditions is sufficient to guarantee that integers $x,$ $y,$ and $z$ satisfy the equation $$
x(x-y)+y(y-z)+z(z-x)
$$$$
= 1?
$$
  1. $ x > y$ and $y=z$
  2. $ x=y-1$ and $y=z-1$
  3. $ x=z+1$ and $y=x+1$
  4. $ x=z$ and $y-1=x$
  5. $ x+y+z=1 $