Answer:
2. 90°
3. 65°
Step-by-step explanation:
2. Points A, B, and D are on a semicircle centered at C. The angle A is inscribed in that semicircle, so is 90°. Then angles B and D sum to 90°.
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3. Triangle ABC is similar to triangle EDC by SAS, so angle x has the same measure as the third angle of triangle EDC: 180° -80° -35° = 65°.
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The relevant relationship in both cases is that the sum of angles in a triangle is 180°. Also, for problem 2, you need to know that an inscribed angle has half the measure of the arc it subtends. And for problem 3, it helps to understand the relationships in similar triangles.
