9514 1404 393
Answer:
- maximum z: 43
- point: (x, y) = (25/7, 9)
Explanation:
In the attached, we have graphed the inequalities and the objective function line. As we might surmise by looking at the constraints,* the maximum occurs at the intersection of y=9 and 7x-y = 16, where (x, y) = (25/7, 9).
The maximum value of z is 7(25/7) +2(9) = 25 +18 = 43.
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The graph shows all inequalities reversed. This has the effect of making the solution space white, rather than buried under 4 levels of shading. As we expect with most "maximize" problems, the feasible region vertex farthest from the origin is the one of interest.
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* The only upper bound on y is y ≤ 9. The only upper bound on x is 7x-y≤16. When we're maximizing some objective function with positive coefficients on the variables, these will be the boundaries of interest.