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OpenStax, Algebra and Trigonometry 2e §12.1 The Ellipse · Exercise 74 · Geometry · Conic sections

The Ellipse · Exercise 74

A person in a whispering gallery standing at one focus of the ellipse can whisper and be heard by a person standing at the other focus because all the sound waves that reach the ceiling are reflected to the other person. If a whispering gallery has a length of 120 feet, and the foci are located 30 feet from the center, find the height of the ceiling at the center.

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OpenStax, Algebra and Trigonometry 2e · §12.1 The Ellipse · Exercise 74

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