document.write( "Question 151324: I am lost with this assignment, HELP! I do not understand hwo these are answered! \r
\n" ); document.write( "\n" ); document.write( "4. A group of students decides to sell pizzas to help raise money for their senior class trip. They sold pepperoni for $12, sausage for $10, and cheese for $8. At the end of their sales the class sold a total of 600 pizzas and made $5900. The students sold 175 more cheese pizzas than sausage pizzas. Set up a system of three equations and three unknowns, use an augmented matrix to solve, and show all work to receive full credit.\r
\n" ); document.write( "\n" ); document.write( "A. What are the three unknowns?
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\n" ); document.write( "\n" ); document.write( "B. Write a separate equation representing each of the first three sentences. \r
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\n" ); document.write( "\n" ); document.write( "C. Determine the augmented matrix that represents the three equations.\r
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\n" ); document.write( "\n" ); document.write( "D. Solve for the matrix. Show all work to receive full credit.\r
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\n" ); document.write( "\n" ); document.write( "E. How many of each type of pizza were sold?
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Algebra.Com's Answer #111240 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Let x=# of pepperoni sold, y=# of sausage sold, and z=# of cheese sold \r
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\n" ); document.write( "\n" ); document.write( "Since there are 3 unknowns, we need 3 equations:\r
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\n" ); document.write( "\n" ); document.write( "Equation #1:\r
\n" ); document.write( "\n" ); document.write( "First, since they sold \"pepperoni for $12, sausage for $10, and cheese for $8\" and collected $5,900, this means that \"12x%2B10y%2B8z=5900\"\r
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\n" ); document.write( "\n" ); document.write( "Equation #2:\r
\n" ); document.write( "\n" ); document.write( "Also, we know that the students sold 600 pizzas total. So this means that the sum of all of the pizzas sold was 600. So this translates to \"x%2By%2Bz=600\". \r
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\n" ); document.write( "\n" ); document.write( "Equation #3:\r
\n" ); document.write( "\n" ); document.write( "Finally, since they sold \"175 more cheese pizzas than sausage pizzas\", this makes the equation \"z=y%2B175\"\r
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\n" ); document.write( "\n" ); document.write( "Getting all of the variables to one side for equation 3 gives us: \"0x-y%2Bz=175\"\r
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\n" ); document.write( "\n" ); document.write( "So we have the system \r
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\n" ); document.write( "\n" ); document.write( "\"system%2812x%2B10y%2B8z=5900%2Cx%2By%2Bz=600%2C0x-y%2Bz=175%29\"\r
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\n" ); document.write( "\n" ); document.write( "This means that we have the augmented matrix matrix\r
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\n" ); document.write( "\n" ); document.write( "\"%28matrix%283%2C4%2C12%2C10%2C8%2C5900%2C1%2C1%2C1%2C600%2C0%2C-1%2C1%2C175%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "d)\r
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\n" ); document.write( "\n" ); document.write( "Solution was generated by the Linear Algebra Toolkit\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=225\", \"y=100\", and \"z=275\" (these values form the right hand column of the augmented matrix).\r
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\n" ); document.write( "\n" ); document.write( "So this means that they sold 225 pepperoni pizzas, 100 sausage pizzas, and 275 cheese pizzas.
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