document.write( "Question 60834This question is from textbook elementry and intermediate algebra
\n" ); document.write( ": This one has me bogged down.\r
\n" ); document.write( "\n" ); document.write( "I am attempting to graph and looking at the table.\r
\n" ); document.write( "\n" ); document.write( "Is this the correct way of looking at this equation?\r
\n" ); document.write( "\n" ); document.write( "The total profit (�P� in dollars) for sales of �x� machines is given by P(x) = - 0.2 x^2 + 300x � 200. Find the following:\r
\n" ); document.write( "\n" ); document.write( "a. The profit if 500 machines are sold.\r
\n" ); document.write( "\n" ); document.write( "b. How many machines must be sold for maximum profit?
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Algebra.Com's Answer #854308 by ikleyn(53804) $\"\"$ $\"About$

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\n" ); document.write( "This question is from textbook elementry and intermediate algebra
\n" ); document.write( "This one has me bogged down.
\n" ); document.write( "I am attempting to graph and looking at the table.
\n" ); document.write( "Is this the correct way of looking at this equation?
\n" ); document.write( "The total profit ('P' in dollars) for sales of 'x' machines is given by P(x) = - 0.2x^2 + 300x - 200.
\n" ); document.write( "Find the following:
\n" ); document.write( "a. The profit if 500 machines are sold.
\n" ); document.write( "b. How many machines must be sold for maximum profit?
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\n" ); document.write( "\n" ); document.write( "        The solution by @consc198 to part (b) is incorrect:\r
\n" ); document.write( "\n" ); document.write( "        his reasoning related to part (b) is WRONG.\r
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\n" ); document.write( "\n" ); document.write( "        For the correct solution to part (b) see what follows.\r
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document.write( "Function P(x) is a quadratic function. It has the leading coefficient negative at x^2.\r\n" );
document.write( "It means that the plot of this quadratic function is a downward parabola, which has the maximum.\r\n" );
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document.write( "The ordinate of the maximum point (the ordinate of the vertex) is \r\n" );
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document.write( "     =  =  =  =  = 750.\r\n" );
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document.write( "Therefore, the maximum profit is\r\n" );
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document.write( "     =  = 112300 dollars.\r\n" );
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document.write( "ANSWER.  For maximum profit, the company should sell 750 machines.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved correctly and completely.\r
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