1998 AMC 12 Problem 28
Attempt Problem 28 of the 1998 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 1998 AMC 12 solutions, or check the answer key.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
28.
In triangle angle is a right angle and Point is located on so that angle is twice angle If then where and are relatively prime positive integers. Find
Answer: B
Small hint:
Let , so and
Big hint:
Set and express and using and
Solution:
Let Since the identity for gives Taking Thus and Therefore so B is correct.
Problem 28 in other years
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