document.write( "Question 289772: Hello can anyone help solve this problem with work shown and answers it will help me learn how to do these problems for my upcoming test.\r
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\n" ); document.write( "\n" ); document.write( "Sean's Widget Company has revenue that is modeled by the function R(x) = -4x2 + 35x and costs modeled by the function C(x) = 12x +30. The input variable x is in hundreds of widgets, and the outputs of the functions are in units of thousands of dollars. Construct a profit function P(x) and find the value of x that maximizes the profit. \r
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\n" ); document.write( "\n" ); document.write( "Thank you John
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Algebra.Com's Answer #209815 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Sean's Widget Company has revenue that is modeled by the
\n" ); document.write( "function R(x) = -4x2 + 35x and costs modeled by the function C(x) = 12x +30.
\n" ); document.write( "The input variable x is in hundreds of widgets, and the outputs of the
\n" ); document.write( "functions are in units of thousands of dollars.
\n" ); document.write( " Construct a profit function P(x) and find the value of x that maximizes the profit.
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\n" ); document.write( "Profit = Revenue - Cost
\n" ); document.write( "P(x) = R(x) - C(x)
\n" ); document.write( "Which is
\n" ); document.write( "P(x) = -4x^2 + 35x - (12x + 30)
\n" ); document.write( "Removing the bracket changes the signs
\n" ); document.write( "P(x) = -4x^2 + 35x - 12x - 30
\n" ); document.write( "Combine like terms
\n" ); document.write( "P(x) = -4x^2 + 23x - 30
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\n" ); document.write( "A quadratic equation, we can find the axis of symmetry: x = -b/(2a)
\n" ); document.write( "That value of x will give us max profit
\n" ); document.write( "x = \"%28-23%29%2F%282%2A-4%29\"
\n" ); document.write( "x = \"%28-23%29%2F%28-8%29\"
\n" ); document.write( "x = +2.875 hundreds of widgets
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\n" ); document.write( " 287.5 ~ 288 widgets for max profit (has to be an integer)
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\n" ); document.write( "To find the actual profit value (in thousands), substitute 2.88 for x in the
\n" ); document.write( "equation P(x) = -4(2.88^2) + 23(2.88) - 30
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