document.write( "Question 1195573: Can I please have help with this, Thank you!
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\n" ); document.write( "Sharon has applied to the navy. She plans to racquetball and cycle to get into shape for the fitness test. Sharon wants to spend no more than 12 hours exercising a week and wants to burn a maximum of 7000 calories. She ahs calculated she will burn 700 calories per hour playing racquetball and 350 calories per hour cycling.\r
\n" ); document.write( "\n" ); document.write( "To describe this scenario, what quantities should x and y represent\r
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\n" ); document.write( "\n" ); document.write( " B. Write a system of inequalities which will represent Sharon’s situation( Hint: three are 4 linear inequalities for this scenario)\r
\n" ); document.write( "\n" ); document.write( "C. Graph the system of inequalities, mark the points of intersection of all lines and shade the solution region.\r
\n" ); document.write( "\n" ); document.write( "D. Bicycling is free but racquetball costs $20 per hour to play. Write the objective function for this scenario. How much time should she spend on each activity in orde to minimize costs?\r
\n" ); document.write( "\n" ); document.write( "E. How much time should she spend on each activity if she just wants to maximize her calorie burn? \r
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\n" ); document.write( "\n" ); document.write( "The diagram has the line 4x+3y=12 dividing the Cartesian Plane into seven regions. Write a system of inequalities the describes region D.
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Algebra.Com's Answer #828115 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
let x = the number of hours playing racquetball.
\n" ); document.write( "let y = the number of hours cycling.
\n" ); document.write( "your inequalities are:
\n" ); document.write( "x + y <= 12
\n" ); document.write( "this represents the total number of hours she wants to use is less than 12.
\n" ); document.write( "700x + 350y <= 7000
\n" ); document.write( "this represents the total number of calories she wants to burn.
\n" ); document.write( "it's 700 calories per hour times the number of hours for racquetball plus 350 calories per hour times the number of hours for cycling.
\n" ); document.write( "x >= 0
\n" ); document.write( "y >= 0
\n" ); document.write( "this represents that the number of hours for each activity can't be less than 0.
\n" ); document.write( "if she wants to minimize costs, then the objective function for costs is:
\n" ); document.write( "20x + 0y, which you want to minimize.
\n" ); document.write( "this represents 20 dollars per hour for racquetball plus 0 dollars for cycling.
\n" ); document.write( "if she wants maximize calories consumed, then the objective function for calories is:
\n" ); document.write( "700x + 350y, which you want to maximize.
\n" ); document.write( "this represents 700 calories per hour times number of hours for racquetball plus 350 calories per hour times number of hours for cycling.
\n" ); document.write( "you can graph this manually, or you can use the calculator at desmos.com.
\n" ); document.write( "if you use the calculator at desmos.com, you would:
\n" ); document.write( "graph the opposite of the inequalities.
\n" ); document.write( "the area of the graph that is not shaded will be your region of feasibility.
\n" ); document.write( "the corner points of the region of feasibility will be where your maximum calory burn and your minimum cost will be.
\n" ); document.write( "objective function for cost is 20x + 0y
\n" ); document.write( "objective function for calories is 700x + 350y
\n" ); document.write( "constraint inequalities are:
\n" ); document.write( "x + y <= 12
\n" ); document.write( "700x + 350y <= 7000
\n" ); document.write( "x >= 0
\n" ); document.write( "y >= 0
\n" ); document.write( "graph the opposite of the inequalities.
\n" ); document.write( "identify the corner points.
\n" ); document.write( "evaluate the objective functions at the corner points.
\n" ); document.write( "the graph looks like this.
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\n" ); document.write( "the corner points of the feasible region are:
\n" ); document.write( "(0,12)
\n" ); document.write( "(8,4)
\n" ); document.write( "(10,0)
\n" ); document.write( "the minimum cost will be at (0,12), where the cost is 20 * 0 + 0 * 12 = 0.
\n" ); document.write( "the maximum calorie burn will be at (10,0) or (8,4).
\n" ); document.write( "at (10,0), the maximum calorie burn is 10 * 700 = 7000
\n" ); document.write( "at (8,4), the maximum calories burn is 8 * 700 + 4 * 350 = 7000.
\n" ); document.write( "you have a minimum cost of 0 and a maximum calorie burn of 7000.
\n" ); document.write( "i have no idea what the equation of 4x + 3y = 12 represents.
\n" ); document.write( "i don't see it as being applicable to this problem, unless there is some other information about the problem that you didn't show.
\n" ); document.write( "if you were to manually create the graph, you would do the following.
\n" ); document.write( "graph the equations of:
\n" ); document.write( "x + y = 12
\n" ); document.write( "700x + 350y = 7000
\n" ); document.write( "x = 0
\n" ); document.write( "y = 0
\n" ); document.write( "you would then shade the areas for the inequalities of:
\n" ); document.write( "x + y <= 12
\n" ); document.write( "700x + 3506 <= 7000
\n" ); document.write( "x >= 0
\n" ); document.write( "y >= 0
\n" ); document.write( "that graph would look like this:
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\n" ); document.write( "using desmos.com calculator, the region of feasibility is the area that is not shaded.
\n" ); document.write( "doing it manually, the region of feasibility is the area that is shaded.
\n" ); document.write( "the region of feasibility is the same, whichever way you wanted to graph it.
\n" ); document.write( "the corner points are the same and the analysis is the same.
\n" ); document.write( "note that, when she minimizes cost, the maximum calorie burn is 12 * 350 = 4200.
\n" ); document.write( "this is acceptable since it is less than 7000, which was one of the constraints.
\n" ); document.write( "all of the constraints need to be satisfied, not just some of them.
\n" ); document.write( "at (0,12), she had exercised for 12 hours which is <= 12 and she had burned 4200 calories which is <= 7000.
\n" ); document.write( "at (8,4), she had exercised for 12 hours which is <= 12 and she had burned 7000 calories which is <= 7000.
\n" ); document.write( "at (10,0), she had exercised for 12 hours which is <= 12 and she had burned 7000 calories which is <= 7000.
\n" ); document.write( "let me know if you have any questions.
\n" ); document.write( "theo
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