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3 years ago

I di not understand these any help greatly appreciated thank you

Mathematics

1 answer:

Rzqust [24]3 years ago

4 0

Answer:

Step-by-step explanation:

First you need to convert it to a linear expression.

3x - y = 4

+3x +3x

-1y = 3x + 4

--- ----- -----

-1 -1 -1

y = -3x -4

6x - 2y = 7

-6x -6x

-2y = -6x + 7

---- ----- -----

-2 -2 -2

y = 3x - 3.5

-3x - 4 = 3x - 3.5

+3x +3x

-4 = 6x - 3.5

+3.5 +3.5

-0.5 = 6x

----- -----

6 6

-0.5

------ = x

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Aleksandr [31]

Answer:

Therefore the circumference of the circle is $=\frac{20\pi}{4+\pi}$

Step-by-step explanation:

Let the side of the square be s

and the radius of the circle be r

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Given that the length of the wire is 20 cm.

According to the problem,

4s + 2πr =20

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Putting the value of s

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$\Rightarrow A= \pi r^2+(\frac{10}{2})^2-2.\frac{10}{2}.\frac{\pi r}{2}+ (\frac{\pi r}{2})^2$

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For maximum or minimum $\frac{dA}{dr}=0$

Differentiating with respect to r

$\frac{dA}{dr}= \frac{2\pi r(4+\pi)}{4} -5\pi$

Again differentiating with respect to r

$\frac{d^2A}{dr^2}=\frac{2\pi (4+\pi)}{4}$ > 0

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$\frac{dA}{dr}=0$

$\Rightarrow \frac{2\pi r(4+\pi)}{4} -5\pi=0$

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2 years ago

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Rom4ik [11]

Answer:

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= 6X = 78

Divide both sides by 6 to solve for X;

X = 78/6

X = 13

And 5X = (5* 13) = 65

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