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lara [203]
8 months ago
13

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 130 feet, and the foci are located 30 feet from the center, find the height of the ceiling at the center. round your answer to 4 decimal places. submit questionquestion 9
Mathematics
1 answer:
Lynna [10]8 months ago
7 0

The Height of the ceiling at the center is  57.6628 feet

In geometry, an ellipse is a two-dimensional shape, that is defined along its axes. An ellipse is formed when a cone is intersected by a plane at an angle with respect to its base.

It has two focal points. The sum of the two distances to the focal point, for all the points in curve, is always constant.

The General form of ellipse is \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1

According to the question,

Length of whispering gallery is 130 feet

The foci are located 30feet from the center (0,0)

So, 2a = 130

=> a = 130/2

=> a = 65

and c = 30

As we know ,

=> c² = a² - b²

=> (30)² = (65)² - b²

=> 900 = 4225 - b²

=> b² = 4225 - 900

=> b² = 3325

=> b = 57.7 feet

Therefore , the height of the ceiling at the center is 57.6628 feet

To know more about Ellipse here

brainly.com/question/19507943

#SPJ4

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5 0
2 years ago
Alberta has 5 shirts and 4 pants. 3 of the shirts are her favorite and 2 of the pants are her favorite. If Alberta chooses an ou
tiny-mole [99]

Answer:

\frac{3}{10}

Step-by-step explanation:

In probability, "AND" means "multiplication" and

"OR" means "addition".

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OlgaM077 [116]
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P(North)=\frac{3C2\times5C0}{8C2}=0.107
The probability that the two will get apartments on the South side is given by:
P(South)=\frac{5C2\times3C0}{8C2}=0.357
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4 0
2 years ago
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3 years ago
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Answer:

7. b

8. a

Step-by-step explanation:

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3 years ago
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