1971 AMC 12 Problem 3
Attempt Problem 3 of the 1971 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 1971 AMC 12 solutions, or check the answer key.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
3.
If the point lies on the straight line joining the points and in the -plane, then is equal to:
Answer: E
Small hint:
Find the slope through the two given fixed points
Big hint:
The line has equation
Solution:
The slope through and is so the line is Substituting gives hence
Therefore, the correct answer is E.
Problem 3 in other years
- 1950 AMC 12
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