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3 years ago

What is the radius of a circle if the area is 78.5 cm^2

Mathematics

1 answer:

Verizon [17]3 years ago

3 0

78.5= (3.14)r^2
25=r^2
5=r
So, the radius of a circle with an area is 78.5 cm^2 is 5 cm^2

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The amount of caffeine in the body can be modeled by the following equation:

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$C(t) = 110e^{-0.1733t}$

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$55 = 110e^{10}$

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Applying ln to both sides

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$10r = \ln{0.5}$

$r = \frac{\ln{0.5}}{10}$

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At 7 pm

7 pm is 11 hours after 8 am, so this is C(11)

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