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1993 AMC 12 Question 25

AMC12 · 1993 AMC 12

Question 25

Let $S$ be the set of points on the rays forming the sides of a $120^\circ$ angle, and let $P$ be a fixed point inside the angle on the angle bisector. Consider all distinct equilateral triangles $PQR$ with $Q$ and $R$ in $S.$ (Points $Q$ and $R$ may be on the same ray, and switching the names of $Q$ and $R$ does not create a distinct triangle.) There are

Question illustration
  1. exactly $2$ such triangles.
  2. exactly $3$ such triangles.
  3. exactly $7$ such triangles.
  4. exactly $15$ such triangles.
  5. more than $15$ such triangles.