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3 years ago

The radius of a circular puddle is growing at a rate of 25 cm/sec.

Mathematics

1 answer:

tatiyna3 years ago

8 0

Answer:

Step-by-step explanation:

a)area A=pi r^2

rate of change of area =dA/dt =2 pi r dr/dt

given dr/dt =25 ,r =50

rate of change of area =dA/dt =2 pi *50 *25 =2500pi=7854

area growing 7854 cm2/s

b)area A=pi r^2

rate of change of area =dA/dt =2 pi r dr/dt

given dr/dt =25 ,A =64

pi r^2 =64

=>r =8/√pi

rate of change of area =dA/dt =2 pi *(8/√pi) *25 =400√pi=708.98

area growing 708.98 cm2/s

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Answer:

$h = 12$

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Step-by-step explanation:

Given

The attached triangle

Required

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This gives:

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2 years ago

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Answer:

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Step-by-step explanation:

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