3 years ago

What are the solutions to this equation? 7x2 − 28 = 0

Mathematics

1 answer:

valentina_108 [34]3 years ago

8 0

Answer:

x = 2 or x = -2

Step-by-step explanation:

7x^2 - 28 = 0

7x^2 = 28

x^2 = 28/7 = 4

x = root(4) or x = -root(4)

x = 2 or x = -2

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Answer:

Step-by-step explanation:

24^2+b^2=25^2

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3 years ago

assume that tge volume,v, of a sphere is expanding at a rate of 100 inches cubex per minute, the volume of a sphere is given by

Zielflug [23.3K]

$\bf \textit{volume of a sphere}\\\\
V=\cfrac{4}{3}\pi r^3\\\\
-----------------------------\\\\
\cfrac{dv}{dt}=\cfrac{4\pi }{3}\cdot 3r^2\cfrac{dr}{dt}\implies \cfrac{dv}{dt}=4\pi r^2\cfrac{dr}{dt}
\\\\\\
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\begin{cases}
\frac{dv}{dt}=100\\\\
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