document.write( "Question 57211This question is from textbook
\n" ); document.write( ": Suppose that the equation p(x) = -2x^2 + 280x - 1000, where x represents the number of items sold, describes the profit function for a certain business. How many itmes should be sold to maximize the profit? \n" ); document.write( "
Algebra.Com's Answer #39091 by ankor@dixie-net.com(22740)\"\" \"About 
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Suppose that the equation p(x) = -2x^2 + 280x - 1000, where x represents the number of items sold, describes the profit function for a certain business. How many itmes should be sold to maximize the profit?
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\n" ); document.write( "p(x) = y
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\n" ); document.write( "This is a quadratic equation, the value of x for a max of y is the vertex, which can be easily found using the vertex formula: x = -b/(2a)
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\n" ); document.write( "In the equation y = -2x^2 + 280x - 1000; a=-2; b=280; c=-1000
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\n" ); document.write( "Using those values in the vertex equation:
\n" ); document.write( "x = -280/(2*-2)
\n" ); document.write( "x = -280/-4
\n" ); document.write( "x = +70 items for max profit
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\n" ); document.write( "If you wish to know the actual amount of profit, substitute 70 for x in the equation: p(x) = -2(70^2) + 280(70) - 1000, you should get $9,700\r
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