In combining inputs x and y, the entrepreneur obtains the maximum output from a given money outlay when
-
\( \begin{matrix} P_ x = P _ y \\ MP _ x = MP _ y \end{matrix} \)
- \(\begin{matrix} MP _ x = P _ x \\ MP _ y = P _ y \end{matrix}\)
- P x. MP x = P y. MP y
- P x P y = MP x. MP y