Company X has decided that they need twice as many model A computers as Model B computers.  How many of each kind of computers can the company buy?

Set up a system of linear equation for each question.  Write each system as an augmented matrix.  You do not have to solve the systems.

• Company X plans to spend $500,000 on 20 new computers. Each model A computer will cost $2,000, each model B $2,500, and each model C $3,500.  Company X has decided that they need twice as many model A computers as Model B computers.  How many of each kind of computers can the company buy?
• A baseball park has 7000 seats. Box seats cost $6, grandstand seats cost $4, and bleacher seats cost $2.  When all seats are sold, the revenue is $26,400.  If the number of box seats is one-third the number of bleacher seats, how many seats of each type are there?
• The population of a state was approximately 24 million in 1980, 30 million in 1990, and 34 million in 2000. Construct a model for this data by finding a quadratic equation whose graph passes through the points (0,24), (10,30), and (20,34).