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3 years ago

7x-6y=18 14x+9y=-27?

Mathematics

1 answer:

Effectus [21]3 years ago

6 0

Answer: Hope this helped(tried my best thinking what the question was asking)

x=0

y=-3

Step-by-step explanation:

(Im going to add and subtract)

Add:

14x-12y=36

14x+9y=-27

28x-3y=9

Subtract:

-14x+12y=-36

14x+9y=-27

21y=-63

y=-3 (substitute in first equation)

7x+18=18

7x=0

x=0

y=-3 and x=0

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where $0\le u\le2\pi$ and $0\le v\le\dfrac\pi/2$ . We then have

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We have

$\dfrac{\partial\mathbf r(u,v)}{\partial u}=\langle-3\sin u\sin v,3\cos u\sin v,0\rangle$
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$=\displaystyle486\pi\int_{w=0}^{w=1}w^3\,\mathrm dw$

where $w=\sin v\implies\mathrm dw=\cos v\,\mathrm dv$ .

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