What is the optimal value of the objective function for this…

Whаt is the оptimаl vаlue оf the оbjective function for this LP? The starting simplex tableau is shown again here for convenience. Equation number Basic variable x1 x2 s1 s2 RHS 0 Z -5 -4 0 0 0 1 s1 2 1 1 0 10 2 s2 1 3 0 1 15