2015 AMC 12A Problem 2
Below is the professionally curated solution for Problem 2 of the 2015 AMC 12A, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2015 AMC 12A solutions, or check the answer key.
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Difficulty rating: 1020
2.
Two of the three sides of a triangle are and Which of the following numbers is not a possible perimeter of the triangle?
Solution:
By the Triangle Inequality, the third side satisfies that is
The perimeter is so it lies strictly between and Among the choices, only falls outside this range.
Thus, the correct answer is E.
Problem 2 in Other Years
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