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3 years ago

The area of a circle is 201cm² . what is the diameter ?

Mathematics

2 answers:

lisabon 2012 [21]3 years ago

8 0

The answer is 16 cm approx.

Diameter= 2 $\sqrt{a/pi}$

=>2 $\sqrt{201 / 22/7}$

=>2 $\sqrt{201*7/22}$

=>15.997.......

=> 16 approx

Hope this helps you!!

seraphim [82]3 years ago

5 0

Answer:

The diameter of the circle is 16

Step-by-step explanation:

$\pi = 3.14$

Area = $\pi r^{2}$ you will have to use this formula to find the radius

$\pi r^{2} = 201$ = $3.14r^{2}=201$ (divide 3.14 into both sides)

$\frac{3.14r^2}{3.14} = \frac{201}{3.14}$ cross out 3.14 leaves you with $r^2$ and divide 201/3.14= 64.01

$r^2 = 64.01\\r = \sqrt{64.01}\\r = 8$ square root 64.01 which equals 8

Diameter = $2r$ 2(8) = 16

To check answer use Area formula $\pi (8)^{2}$ = 201. 0619298

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3 years ago

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3 years ago

Find the center and radius of the circle whose equation is x 2 + y 2 + 10x − 1

Margaret [11]

we conclude that the center of the circle is the point (-5, 0).

<h3>How to find the center of the circle equation?</h3>

The equation of a circle with a center (a, b) and a radius R is given by:

$(x - a)^2 + (y - b)^2 = R^2$

Here we are given the equation:

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Completing squares, we get:

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Now we can add and subtract 25 to get:

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If you want to learn more about circles:

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2 years ago

Pls help trig question!!

s2008m [1.1K]

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2 years ago

Help me with this please

Elina [12.6K]

Answer:

1) <2 ; 60

2) <3 ; 60

3) <4 and <3. <4 = 120 and <3 = 60

4) <1, <3, and <4 = 125. <2 = 55

Step-by-step explanation:

Corresponding angles are equal

Alternate interior angles are equal

<4 and <3 are same-side interior angles. This makes them supplementary angles

<4 = 120

<3 = 60

<1 = <4 = <3. All of these angles equal 125.

<2 + <1 = 180

<2 + 125 = 180

<2 = 55

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3 years ago