1981 AMC 12 Problem 2
Attempt Problem 2 of the 1981 AMC 12 below, then check your answer against the professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 1981 AMC 12 solutions, or check the answer key.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
2.
Point is on side of square If has length one and has length two, then the area of the square is
Answer: C
Small hint:
Triangle is a right triangle
Big hint:
The unknown leg is also the side length of the square
Solution:
Let the square’s side length be In right triangle Hence which is exactly the area of the square.
Therefore, the correct answer is C.
Problem 2 in other years
- 1950 AMC 12
- 1951 AMC 12
- 1952 AMC 12
- 1953 AMC 12
- 1954 AMC 12
- 1955 AMC 12
- 1956 AMC 12
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