Official Guide Explanation:
Problem Solving #44




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Solution and Metadata

Question: 44
Page: 67
Difficulty: 5 (Moderate)
Category 1: Geometry > Triangles > other
Category 2: Geometry > Triangles > Multiple figures

Explanation: It's tempting to treat this diagram as two separate triangles, but it's much simpler to think of it as one, with angles x, 70, and (37 + z). Since a triangle contains a total of 180 degrees, we can say that 180 = x + 70 + (37 + z), or 180 = 107 + x + z. To solve for x: x = 180 - 107 - z = 73 - z, choice (E).

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