2011 AMC 8 Problem 20
Attempt Problem 20 of the 2011 AMC 8 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 2011 AMC 8 solutions, or check the answer key.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
20.
Quadrilateral is a trapezoid, and the altitude is What is the area of the trapezoid?
Answer: D
Small hint:
Use -- and -- right triangles.
Big hint:
Drop perpendiculars from the top vertices to the base.
Solution:
We can drop the following altitudes to more easily find the area.
We can use the Pythagorean Theorem to get that and
We also know that so
Then the area of is
Thus, D is the correct answer.
Problem 20 in other years
- 1985 AMC 8
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