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How do you solve for r in #V=πr^2h#?

Answer 1

Nathan Axel

#r=sqrt(V/(pih))#

Step 1. Divide both sides by #pi#

#V/pi=(cancel(pi)r^2h)/cancel(pi)=r^2h#

Step 2. Divide both sides by #h#

#V/(pih)=(r^2cancel(h))/cancel(h)=r^2#

Step 3. Take #+-sqrt()# both sides

#+-sqrt(V/(pih))=r#

Step 4. Radius, #r#, is not a negative value, so just keep the positive

#r=sqrt(V/(pih))#

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Answer 2

Eva Adamson

To solve for ( r ) in the formula ( V = \pi r^2h ), you can rearrange the equation as follows:

[ V = \pi r^2h ] [ \frac{V}{\pi h} = r^2 ] [ r = \sqrt{\frac{V}{\pi h}} ]

So, to solve for ( r ), you take the square root of ( \frac{V}{\pi h} ).

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.