This Primal Min LPmin$=31+22+3$s$.$t$\mathrm{.}1+2+342321+2+23=61,2,30$ has dual$$max$=41+22+63$s$.$t$\mathrm{.}1+331+2+3212+23110,20,3$ursOprah says that Row$0$ of the optimal Primal tableau is:$[1231213$rhs$110030316]$But since the Primal is a Min, the dual is a max and so weRead$=[123]=1$as usual from the optimal tableau,When the primal is a min the values of dual optimal$$are still readable from row$0$ of the optimal tableau in the same way:$$is the value under$$; or the negative under$$; or$,$ if needed, the value under$$after deleting Big$-$M$.($here$$means coefficients from$$; called it$$in Dual Theorem$)(1)$ for convenience, written horizontally:$[123]=[]$This time we are checking that this$$is dual feasible:$(2)$ plugging into the first dual constraint, left side equals$(3)$ Plugging into the second dual constraint, left side equals$(4)$ Plugging into the third dual constraint, left side equals$$