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2 years ago

A 42" diameter table needs a tablecloth that hangs off the edge 8". What is the area of the tablecloth? Use 3.14 for π.

2 answers:

6 0

The diameter of the table is 42 inches. The radius of the table is half of the diameter of the table, so the radius of the table is 42/2 = 21 inches.

Add on 8 inches to the table radius to get: 21+8 = 29

So the radius of the table cloth is r = 29

Plug this into the area of a circle formula

A = pi*r^2
A = pi*29^2
A = pi*841
A = 841pi
A = 841*3.14
A = 2640.74

The approximate area of the table cloth is 2640.74 square inches.

-Dominant- [34]2 years ago

6 0

The area of the table cloth is 2,640.74 iches

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Answer:

Missing side = x+2

Step-by-step explanation:

The perimeter of the classroom, 6x+3, is equal to the 4 side lengths added up.

In their first line of work, the first plus sign should be an equal sign as follows:

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1 year ago

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$\displaystyle \int \frac{x^3}{\sqrt{1-x^2}} \, dx = \int \frac{\sin^3(\theta)}{\cos(\theta)} \cos(\theta) \, d\theta = \int \sin^3(\theta) \, d\theta$

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$\sin^3(\theta) = \sin(\theta) \sin^2(\theta) = \sin(\theta) (1 - \cos^2(\theta))$

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Replace the variable to get the antiderivative back in terms of x and we have

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since, like in the previous integral, under this reversible variable change we assume -π/2 < θ < π/2. Over this interval, sec(θ) is positive.

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and substitute $y=\cos(\theta)$ again to get

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Put everything back in terms of x :

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