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F is inversely proportional to √ g . When f = 8 , g = 81 Work out g when f = 4

User Nedzad
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5 votes

Answer:

Explanation:

The question is basically saying that f is equal to
(k)/(√(g) )

when f=8, g=81. Therefore 8=
(k)/(√(81) ) =(k)/(9).

Then the next step is to simplify the equation, so k = 72.

The next step is to plug k=72 back into the original equation.

f=
(72)/(√(g) )

Then you do the last step which is to plug f=4 into the equation which will result in 4=72/sqrt(g) => 4*sqrt (g) =72. Therefore sqrt (g) = 72/4 = 18. Then you square both sides and you get g=324.

User Nick Hutchinson
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