document.write( "Question 173706: Please show me how to solve. I'm having trouble understanding from when I asked a few days ago.\r
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document.write( "Solve by graphing.
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document.write( "3x + 4y ≤ 12
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document.write( "x + 3y ≤ 6
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document.write( "x ≥ 0
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document.write( "y ≥ 0 \n" );
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Algebra.Com's Answer #128625 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! Solve by graphing. \n" ); document.write( "3x + 4y ≤ 12 \n" ); document.write( "x + 3y ≤ 6 \n" ); document.write( "x ≥ 0 \n" ); document.write( "y ≥ 0\r \n" ); document.write( "\n" ); document.write( ": \n" ); document.write( "Plot the 1st two equations, put the equations in the slope/intercept form \n" ); document.write( "3x + 4y =< 12 \n" ); document.write( "4y = 12 - 3x \n" ); document.write( "y = \n" ); document.write( "y = \n" ); document.write( ": \n" ); document.write( "Calculate two points (substitute the values for x and find y): \n" ); document.write( " x | y \n" ); document.write( "------- \n" ); document.write( " 0 | 4 \n" ); document.write( " 4 | 1 \n" ); document.write( "Graph should look like this: \n" ); document.write( " \n" ); document.write( ": \n" ); document.write( "Do the same with the 2nd equation \n" ); document.write( "x + 3y => 6 \n" ); document.write( "3y = 6 - x \n" ); document.write( "y = \n" ); document.write( "y = - \n" ); document.write( "Calculate two points (substitute the values for x and find y): \n" ); document.write( " x | y \n" ); document.write( "------- \n" ); document.write( " 0 | 2 \n" ); document.write( " 3 | 1 \n" ); document.write( "Graph should look like this: \n" ); document.write( " \n" ); document.write( ": \n" ); document.write( "The last two equations tell you that only positive values for x and y are considered \n" ); document.write( ": \n" ); document.write( "Put both graphs on the same coordinate system: \n" ); document.write( " \n" ); document.write( "Look at this graph \n" ); document.write( "The 1st equation:3x + 4y =< ; 12, the purple line \n" ); document.write( "Area of feasibility is at or below this line \n" ); document.write( ": \n" ); document.write( "The 2nd equation: x + 3y => 6, green line \n" ); document.write( "Area of feasibility is at or above this line \n" ); document.write( ": \n" ); document.write( "x => 0 \n" ); document.write( "y => 0 \n" ); document.write( "As I said before, this means only positive values for x & y, inside the area of feasibility are considered. \n" ); document.write( ": \n" ); document.write( "The solution is the triangular area between the lines and to the right of the y axis. \n" ); document.write( " |