Official Guide Explanation:
Problem Solving #30




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Solution and Metadata

Question: 30
Page: 65
Difficulty: 5 (Moderate)
Category 1: Geometry > Intersecting Lines and Angles >
Category 2: Algebra > Linear Equations-Two Unk >

Explanation: You're given one equation, and the diagram gives you the other. The sum of the degrees in a straight line in 180, so x + y = 180. Plug that into the other equation, and your result is ((x)/180) = (3/8). Simplify by cross - multiplying: 8x = 180(3) = 540. The final steps: x = (540/8) = (270/4) = (135/2) = 67.5, choice (B).

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