Question 1147061
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1-st constraint  x + y <= 8.

     Consider equation  x + y = 8  and plot the line  y = 8-x.

                                       Do it ON YOUR OWN.




2-nd constraint  5x + y <= 20.

      Consider equation  5x + y = 20  and plot the line y = 20 - 5x.

                                       DO IT ON YOUR OWN.



3-rd constraint  x >= 0.   

      It is LEFT half-plane (everything to the left of y-axis).




4-th constraint  y >= 0.   

      It is UPPER half-plane (everything above the x-axis).



The 3-rd and the 4-th constraint together define (is) Quadrant I.




P = 6x + 4y is the profit function (or "objective" function).

     We do not plot it.



Now your domain is the quadrilateral in the first quadrant under 

    the line  y = 8 - x  and  the line   y = 20-5x.
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I answered all your questions.


Make the plot and REPORT me if everything is clear to you . . . 


If you will respond, refer to the problem ID number  1147061.


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    Otherwise I will not know to which problem relates your response.
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