Chapter 8: Problem 90
When using the addition or substitution method, how can you tell if a system of linear equations has infinitely many solutions? What is the relationship between the graphs of the two equations?
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Chapter 8: Problem 90
When using the addition or substitution method, how can you tell if a system of linear equations has infinitely many solutions? What is the relationship between the graphs of the two equations?
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A television manufacturer makes rear-projection and plasma televisions. The profit per unit is 125 for the rear-projection televisions and 200 for the plasma televisions. a. Let \(x=\) the number of rear-projection televisions manufactured in a month and let \(y=\) the number of plasma televisions manufactured in a month. Write the objective function that models the total monthly profit. b. The manufacturer is bound by the following constraints: \(\cdot\) Equipment in the factory allows for making at most 450 rear-projection televisions in one month. \(\cdot\) Equipment in the factory allows for making at most 200 plasma televisions in one month. \(\cdot\) The cost to the manufacturer per unit is 600 for the rear-projection televisions and 900 for the plasma televisions. Total monthly costs cannot exceed 360,000. Write a system of three inequalities that models these constraints. c. Graph the system of inequalities in part (b). Use only the first quadrant and its boundary, because \(x\) and \(y\) must both be nonnegative. d. Evaluate the objective function for total monthly profit at each of the five vertices of the graphed region. [The vertices should occur at \((0,0),(0,200),(300,200)\) \((450,100), \text { and }(450,0) .]\) e. Complete the missing portions of this statement: The television manufacturer will make the greatest profit by manufacturing _____ rear- projection televisions each month and _____ \(-\) plasma televisions each month. The maximum monthly profit is $_____.
Determine whether each statement makes sense or does not make sense, and explain your reasoning. Even if a linear system has a solution set involving fractions, such as \(\left\\{\left(\frac{8}{11}, \frac{43}{11}\right)\right\\},\) I can use graphs to determine if the solution set is reasonable.
A company that manufactures small canoes has a fixed cost of \(\$ 18,000 .\) It costs \(\$ 20\) to produce each canoe. The selling price is \(\$ 80\) per canoe. (In solving this exercise, let \(x\) represent the number of canoes produced and sold.)
Use the two steps for solving a linear programming problem, given in the box on page \(888,\) to solve the problems. You are about to take a test that contains computation problems worth 6 points each and word problems worth 10 points each. You can do a computation problem in 2 minutes and a word problem in 4 minutes. You have 40 minutes to take the test and may answer no more than 12 problems. Assuming you answer all the problems attempted correctly, how many of each type of problem must you answer to maximize your score? What is the maximum score?
Write a system of equations having {(-2, 7)} as a solution set. (More than one system is possible.)
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