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2 years ago

Find the area and the circumference of a circle with diameter 6 km

Mathematics

1 answer:

mash [69]2 years ago

4 0

Answer:

$C= 18.84 \ km$

$A = 28.26 \ km$

Step-by-step explanation:

Circumference can be calculated using following formula

$C=2\pi r$ ------------(1)

and area of circle can be calculated using following formula

$A= \pi r^{2}$ ------------(2)

Here diameter d=6 km

Radius (r) is half of diameter

$r= \frac{d}{2} = \frac{6}{2} = 3 \ km$

Now calculate Circumference and diameter using equations (1) and (2) respectively

$C= 2\pi r = 2 (3.14) (3)\\C= 18.84 \ km$

$A= 3.14 (3)^2\\A= 28.26 \ km$

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8. You are planning to use a ceramic tile design in your new bathroom. The tiles are blue-and-white equilateral triangles. You d

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Someone please be awesome and help me please :(

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Answer:

$(x+\frac{b}{2a})^2+(\frac{4ac}{4a^2}-\frac{b^2}{4a^2})=0$

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Step-by-step explanation:

$x^2+\frac{b}{a}x+\frac{c}{a}=0$

They wanted to complete the square so they took the thing in front of x and divided by 2 then squared. Whatever you add in, you must take out.

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Now we are read to write that one part (the first three terms together) as a square:

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I don't see this but what happens if we find a common denominator for those 2 terms after the square. (b/2a)^2=b^2/4a^2 so we need to multiply that one fraction by 4a/4a.

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