document.write( "Question 129106: 1. A company that produces cells for solar collectors finds through experience that on the average it can sell x cells per day at a selling price (in dollars) of p(x) = 100 – 0.05x (p is called the demand function). The cost function C(x) for producing x cells per day is C(x)= 4000 + 60x – 0.01x^2\r
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\n" ); document.write( "\n" ); document.write( "A. Write the revenue function R(x).\r
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\n" ); document.write( "\n" ); document.write( "C. Find the value of x that maximizes profit, and find the maximum profit.
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Algebra.Com's Answer #94373 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
a)\r
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\n" ); document.write( "\n" ); document.write( "The revenue can be found by this general formula:\r
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\n" ); document.write( "\n" ); document.write( "Revenue=Number of units sold*price of each unit\r
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\n" ); document.write( "\n" ); document.write( "So in our case, \"R%28x%29=x%2AP%28x%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"R%28x%29=x%2AP%28x%29\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"R%28x%29=x%2A%28100-0.05x%29\" Plug in \"P%28x%29+=+100+%96+0.05x\"\r
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\n" ); document.write( "\n" ); document.write( "\"R%28x%29=100x-0.05x%5E2\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"R%28x%29=-0.05x%5E2%2B100x+\" Rearrange the terms\r
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\n" ); document.write( "\n" ); document.write( "So the revenue function is \r
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\n" ); document.write( "\n" ); document.write( "\"R%28x%29=-0.05x%5E2%2B100x+\"\r
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\n" ); document.write( "\n" ); document.write( "b)\r
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\n" ); document.write( "\n" ); document.write( "The profit can be found by:\r
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\n" ); document.write( "\n" ); document.write( "Profit=Revenue-Cost\r
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\n" ); document.write( "\n" ); document.write( "So \r
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\n" ); document.write( "\n" ); document.write( "\"P%28x%29=R%28x%29-C%28x%29\" \r
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\n" ); document.write( "\n" ); document.write( "\"P%28x%29=%28-0.05x%5E2%2B100x%29-%284000+%2B+60x-0.01x%5E2%29\" Plug in \"R%28x%29=-0.05x%5E2%2B100x+\" and \"C%28x%29=4000+%2B+60x+%96+0.01x%5E2\" \r
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\n" ); document.write( "\n" ); document.write( "\"P%28x%29=-0.05x%5E2%2B100x-4000-60x+%2B+0.01x%5E2\" Distribute the negative\r
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\n" ); document.write( "\n" ); document.write( "\"P%28x%29=-0.04x%5E2%2B40x-4000\" Combine like terms\r
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\r
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\n" ); document.write( "\n" ); document.write( "To find the max profit, we need to graph the profit function \"P%28x%29=-0.04x%5E2%2B40x-4000\"\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C-740%2C1260%2C-10523%2C7649%2C-0.04x%5E2%2B40x-4000%29\"\r
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\n" ); document.write( "\n" ); document.write( "And by using the calculators vertex function, we find that the vertex occurs at \"x=500\"\r
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\n" ); document.write( "\n" ); document.write( "Now plug in \"x=500\" into \"P%28x%29=-0.04x%5E2%2B40x-4000\"\r
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\n" ); document.write( "\n" ); document.write( "\"P%28x%29=-0.04%28500%29%5E2%2B40%28500%29-4000\"\r
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\n" ); document.write( "\n" ); document.write( "\"P%28x%29=6000\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So the maximum profit is $6,000
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