Question 990710
<i>V=1/3(pie r squared)H</i>
That must  be wrong because you should mean, "cubed".


The pure text,
V=(1/3)pi*r^3*H


{{{V=(1/3)pi*r^3*H}}}


The multiplicative inverse necessary for the multiplication property of equality is  {{{3/(pi*r^3)}}};
You can perform the step and simplification, 
and then to indicated substitutions to evaluate H.