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haleyelizabeth2017

  • one year ago

Find the minimum value of the function for the polygonal convex set determined by the given system of inequalities. Please no direct answers.

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  1. haleyelizabeth2017
    • one year ago
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    \(2x+2y\ge 16\) \(-2x+6y\le 24\) \(-4x+4y\ge -8\) \(f(x,y)=5x+4y\)

  2. haleyelizabeth2017
    • one year ago
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    @phi think you can help?

  3. aaronq
    • one year ago
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    I dont really remember how to do this and i dont want to give you a crappy answer, buti think this video may be helpful https://www.youtube.com/watch?v=RPuhkQ0vGK0

  4. haleyelizabeth2017
    • one year ago
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    Perhaps...that's the next lesson I have....

  5. phi
    • one year ago
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    How far did you get? I think you plot the relations, and find the intersection points then at each intersection point, evaluate the function f(x,y)

  6. haleyelizabeth2017
    • one year ago
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    Ah...I'm still watching video lol

  7. haleyelizabeth2017
    • one year ago
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    Graphing inequalities now...

  8. haleyelizabeth2017
    • one year ago
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    The next step the dude shows is confusing..."cover up the x"?

  9. phi
    • one year ago
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    I used geogebra to plot them

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  10. haleyelizabeth2017
    • one year ago
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    okay

  11. phi
    • one year ago
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    that is the hard part, finding the intersection points once you have them, you have (x,y) pairs that you "evaluate" using f(x,y) = 5x+4y

  12. haleyelizabeth2017
    • one year ago
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    Okay, the inequalities intersect at (3,5), (9,7), (5,3).

  13. phi
    • one year ago
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    yes. now check each pair

  14. haleyelizabeth2017
    • one year ago
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    Do I plug them into the equation?

  15. phi
    • one year ago
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    yes.

  16. haleyelizabeth2017
    • one year ago
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    f(3,5)=35

  17. phi
    • one year ago
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    at every point on the graph f(x,y) has a value. But the max or min values will always occur at one of the vertexes (intersection points of the boundaries) so we test each vertex. One will be the min and that is the pair we pick

  18. haleyelizabeth2017
    • one year ago
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    Ah hah

  19. phi
    • one year ago
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    Did you do the other 2 pairs?

  20. haleyelizabeth2017
    • one year ago
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    Minimum is at (3,5) :)

  21. haleyelizabeth2017
    • one year ago
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    Yes! f(9,7)=73 and f(5,3)=37 :D

  22. haleyelizabeth2017
    • one year ago
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    That seems easier than I thought it would be...

  23. phi
    • one year ago
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    what did you get for (5,3) ?

  24. haleyelizabeth2017
    • one year ago
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    37....

  25. phi
    • one year ago
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    dyslexia strikes again!

  26. haleyelizabeth2017
    • one year ago
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    aw

  27. haleyelizabeth2017
    • one year ago
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    Mind helping me with a couple more?

  28. haleyelizabeth2017
    • one year ago
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    It's probably easier than I think it will be...brain isn't working today lol

  29. phi
    • one year ago
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    no, my brain was not working and I confused 5,3 and 3,5 but yes, the answer is at 3,5 they want Find the minimum value of the function , so 35 is the answer

  30. phi
    • one year ago
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    The painful part of these problems is plotting the relations, and finding the intersection points. If you can use something like geogebra or other such tools, then the problems are not too hard.

  31. haleyelizabeth2017
    • one year ago
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    Lol the next ones I have to plot two inequalities and state which numbered region or regions belong to the solution...

  32. haleyelizabeth2017
    • one year ago
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    After you showed me what to do, that one was pretty easy :)

  33. haleyelizabeth2017
    • one year ago
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    Thank you, by the way :)

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