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3 years ago

How to find the area of a circle with the circumference?

1 answer:

5 0

You can abuse the fact that PI is Circumference/diameter.

This means that, to find the diameter, you would have to do the following:

PI = circumference/diameter
(You can choose the number of decimals of PI, based on how accurate you want the diameter. 3.14 tends to work for most cases.)

After youve done this, you would be able to find the diameter like this:
PI*diameter = circumference
diameter = Circumference/pi

Then, you can use the diameter/2 to find the radius, like this:
radius = diameter/2

After this, you can simply use the formula for the surface area of a circle, like this:

SA = PI*Radius^2

I might be able to add an example, if really needed.

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a bag of 28 tulip cointains 11 red tulip, 8yellow tulip buibs and 9purple tulip bulbs. Suppose two are randomly selected . What

Tcecarenko [31]

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3 years ago

Nadia finds out that her favorite horse family population is increasing at a constant rate. The horse family was at 24 in 2011 a

Dahasolnce [82]

$\begin{gathered} y-24=\frac{8}{3}(x-2011) \\ \text{There will be 48 horses in 2020 (option A)} \end{gathered}$ Explanation:

The initial number of horses = 24

year = 2011

Coordinates (2011, 24)

when the number of horses became 32, year was 2014

Coordinates (2014, 32)

We find the slope = rate of change

slope = change in number of horses/change in number of years

slope = (32-24)/(2014-2011)

slope = 8/3

The point slope formula:

$\begin{gathered} y-y_1=m(x-x_1) \\ U\sin gpoint\colon x_1=2011,y_1=24 \end{gathered}$ $y-24=\frac{8}{3}(x-2011)$

The number of horses in year 2020

using points: (2011, 24) and (2020, y), we equate with the slope since it is constant for any two points on this model.

8/3 = (y - 24)/(2020 - 2011)

8/3 = (y - 24)/9

cross multiply:

8(9) = 3(y - 24)

72 = 3y - 72

72 + 72 = 3y

144 = 3y

144/3 = 3y/3

y = 48

Hence, there will be 48horses in 2020 (option A)

4 0

1 year ago

For my homework i dont understand this: the sale price on an item is $160 after a 20% discount.what is the origonal price of the

mr_godi [17]

The original price is $200 because if you did 200 * 0.2, it would equal $160 which is the discounted price.

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4 years ago

I need help finding missing angles

vagabundo [1.1K]

Ok. Could I have a picture of the question? :)

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3 years ago

Need help checking my answers

kifflom [539]

Answer:

Step-by-step explanation:

_______

Good evening ,

______________

Look at the photo below for the answer,

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3 years ago