1999 AMC 12 Problem 2
Below is the professionally curated solution for Problem 2 of the 1999 AMC 12, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 1999 AMC 12 solutions, or check the answer key.
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Difficulty rating: 880
2.
Which one of the following statements is false?
All equilateral triangles are congruent to each other.
All equilateral triangles are convex.
All equilateral triangles are equiangular.
All equilateral triangles are regular polygons.
All equilateral triangles are similar to each other.
Solution:
Equilateral triangles with side lengths and have the same shape but different sizes, so they are similar but not congruent. Every equilateral triangle is convex, equiangular (all angles ), and a regular polygon, so the only false statement is that they are all congruent.
Thus, the correct answer is A.
Problem 2 in Other Years
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