Hi Michael,

Looking at the equations

\begin{eqnarray*}
2P &+& \frac13 V &=& 8\\
3P &-& \frac{2}{V} &=&5.
\end{eqnarray*}

The immediate task is to eliminate one of the variables so that you have one equation in one unknown. You can achieve this by multiplying the first equation by 3 and the second equation by 2. This will result in two equations with the same coefficient for $P.$ Then if you subtract the two equations you will be left with one equation in the variable $V.$

Try this and if you need further help let us know what you got and where you are stuck,
Penny