Official Guide Explanation:
Problem Solving #145




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Solution and Metadata

Question: 145
Page: 172
Difficulty: 6 (Moderately Difficult)
Category 1: Geometry > Quadrilaterals >
Category 2: Geometry > Triangles > Pythag
Category 3: Geometry > Triangles > Multiple figures

Explanation: The distance AB can be seen as the hypotenuse of a right triangle consisting of the bottom of the rudder and the right side, which measures 5 feet. Since AB =13, you should recognize that this is a common pythagorean ratio of 5:12:13. Without having to do the math, you can immediately determine that the bottom of the rudder is 12 feet. The area of a trapezoid is w(((h1 + h2)/2)), which in this case is 12(((5 + 2)/2)) = ((12(7))/2) = 6(7) = 42, choice (C).

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