River
From the observatory 11 m high and 24 m from the riverbank, river width appears in the visual angle φ = 13°. Calculate the width of the river.
Correct answer:
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You need to know the following knowledge to solve this word math problem:
- algebra
- equation
- planimetrics
- Pythagorean theorem
- right triangle
- triangle
- The Law of Sines
- basic functions
- reason
- goniometry and trigonometry
- tangent
- arctangent
Units of physical quantities:
Grade of the word problem:
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