Question

Make 'r' the subject of the formula: v = 4alt=" \pi " align="absmiddle" class="latex-formula">r²h

(Thanks!)

Answer 1

v = 4π r²h is to be solved for r.

Divide both sides of this equation by 4π*h:

     v

--------- = r^2

   4π*h

Next, take the positive square root of both sides:

              v

r = √[----------- ]

           4π*h

You may leave this result as is, or proceed further:  Taking the + square root of 4 results in:

                      v

r = (1/2)√[----------- ]

                    π*h

Answer 2

$V=4\pi r^2h\\\\ r^2=\dfrac{V}{4\pi h }\\\\ r=\sqrt{\dfrac{V}{4\pi h }}\\\\ r=\dfrac{\sqrt V}{\sqrt{4\pi h} }\\\\ r=\dfrac{\sqrt V}{2\sqrt{\pi h} }\\\\ r=\dfrac{\sqrt {\pi h V}}{2}$