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max2010maxim [7]
2 years ago
9

What is the diameter of a circle with the equation x2 + y2 - 8x + 2y - 8 = 0?

Mathematics
2 answers:
Zinaida [17]2 years ago
7 0

Answer:

50

Step-by-step explanation:

x2 + y2 - 8x + 2y - 8 = 0

first we find the radius with the equation.

write the equation in standard form.

x2 + y2 - 8x + 2y - 8 = 0

(x-4)^2 + (y+1)^2 = 25

(x-h)² + (y-k)² = r²

this means 25 is the radius and the diameter is two times the radius so,

25 x 2 = 50

bazaltina [42]2 years ago
6 0

Answer:

Diameter is 10 units

Step-by-step explanation:

<u>Convert standard form to general form by completing the square:</u>

x^2+y^2-8x+2y-8=0

x^2-8x+y^2+2y-8=0

x^2-8x+y^2+2y=8

x^2-8x+16+y^2+2y+1=8+16+1

(x-4)^2+(y+1)^2=25

(x-4)^2+(y+1)^2=5^2

So, since the radius of the circle is 5 units, then the diameter is twice the radius, which is 10 units.

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Allometric relations often can be modeled by ​f(x)= x^b​, where a and b are constants. One study showed that for a male fiddler
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Answer:

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Dividing both sides by 0.448 we got:

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We can appy the exponent \frac{1}{1.21} in both sides of the equation and we got:

(\frac{0.5}{0.448})^{\frac{1}{1.21}} = x= 1.095grams

Step-by-step explanation:

For this case we know the following function:

f(x) = 0.448 x^{1.21}

The notation is: x is the weight of the crab in​ grams, and the output​ f(x) is the weight of the claws in grams.

Part a

For this case we just need to replace x = 2 gram in the function and we got:

f(2)= 0.448 (2)^{1.21}= 1.036 grams

Part b

For this case we know tha value for f(x) =0.5 and we want to find the value of x who satisfy this condition:

0.5 = 0.448 x^{1.21}

Dividing both sides by 0.448 we got:

\frac{0.5}{0.448} = x^{1.21}

We can appy the exponent \frac{1}{1.21} in both sides of the equation and we got:

(\frac{0.5}{0.448})^{\frac{1}{1.21}} = x= 1.095grams

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Find the area of a circle with a diameter of four
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Answer:

12.57

Step-by-step explanation:

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Read 2 more answers
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vivado [14]

Answer:

The answer to the question is;

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Number of tickets sold = 105 tickets

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