document.write( "Question 1168379: use the graphical method to maximize: z = x+y
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document.write( "Subject to: x+2y<12, 2x+y<12, x>0, y>0 \n" );
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Algebra.Com's Answer #792999 by Theo(13342)![]() ![]() You can put this solution on YOUR website! z = x + y is your objective function.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "subject to inequalities are your constraints.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "using the desmos.com calculator, you would graph the opposite of the inequalities.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the area on the graph that is not shaded is the region of feasibility.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the corner points of this region are where your maximum values of the objective function will be.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the corner points are in (x,y) format.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "evaluate x + y using the values at each corner point.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the corner point with the greatest value of x + y is your maximum value of x + y.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the graph looks like this.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "your points are at (0,6), (4,4), (6,0), (0,0)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "your values of x + y at these points are 6, 8, 6, 0\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "if the points are allowed to be on the lines, your maximum value would be 8.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "because the points can't be on the lines, your maximum value will be some value less than 8.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that's still the maximum value because all the other values are less than a maximum number that is less than 8.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "fyi, i put this in a simplex modeling tool that is used to solve problems like this and it said it can't deal with <; it can only deal with <=.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "i graphed the inequalities as <= or >=.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the corner points are the same as when i graphed the inequalities as < or >.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "it's the evaluation at those corner points that counts.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "if all inequalities were <=, then the value at the corner point is valid.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "if some or all the inequalities were <, then the value at the corner point needs to be checked to see that all the inequalities are satisfied at that corner point.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the simplex modeling tool i used is at:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "https://www.zweigmedia.com/RealWorld/simplex.html\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the desmos.com graphing calculator that i used is at:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "https://www.desmos.com/calculator\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "here's a display of the graphing method in the two forms described above (using <= and using <) to show you that the corner points are the same.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "here's a display of the results using the simplex modeling tool in the two forms describe above to show you that the simplex modeling tool could handle <= and couldn't can't handle <.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |