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2011 AMC 12B Question 23

AMC12 · 2011 AMC 12B

Question 23

A bug travels in the coordinate plane, moving only along the lines that are parallel to the $x$-axis or $y$-axis. Let $A=(-3, 2)$ and $B=(3, -2).$ Consider all possible paths of the bug from $A$ to $B$ of length at most $20.$ How many points with integer coordinates lie on at least one of these paths?
  1. $161$
  2. $185$
  3. $195$
  4. $227$
  5. $255$