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Notes

• Subtopic: Identifying the Triangle Type Notes: Use Trigonometry to Find Missing Sides Given a triangle with hypotenuse 20 and a 30° angle, the goal is to find sides a and b. Two approaches are: • Recognize it as a 30-60-90 triangle with sides in ratio 1 : √3 : 2: - a (opposite 30°): half of hypotenuse, so a = 10. - b (opposite 60°): √3 times a, so b = 10√3. • Or apply trigonometric ratios: - sin(30°) = a/20 → a = 10. - cos(30°) = b/20 → b = 10√3. Both methods confirm the side lengths.