document.write( "Question 138710: \"A company calculates it's profit by finding the difference between
\n" ); document.write( "revenue and cost. The cost function of producing x hammers is C(x) =
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\n" ); document.write( "selling x hammers is R (x) = 10x.\"
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\n" ); document.write( "1.) How many hammers must be sold to make a profit?
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\n" ); document.write( "2.) How many hammers must be sold to make a profit of $100?
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Algebra.Com's Answer #101212 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "The profit function is defined 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 in function notation it looks like:\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( "So in our case:\r
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\n" ); document.write( "\n" ); document.write( "\"P%28x%29=10x-%284x%2B170%29\" Plug in \"R%28x%29=10x\" and \"C%28x%29=4x%2B170\"\r
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\n" ); document.write( "\n" ); document.write( "\"P%28x%29=10x-4x-170\" Distribute the negative\r
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\n" ); document.write( "\n" ); document.write( "\"P%28x%29=6x-170\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "\"6x-170%3E0\" Set the right side greater than zero. Remember we're looking for positive profit.\r
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\n" ); document.write( "\n" ); document.write( "\"6x%3E170\" Add 170 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x%3E170%2F6\" Divide both sides by 6\r
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\n" ); document.write( "\n" ); document.write( "\"x%3E28.333\" Divide \r
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\n" ); document.write( "\n" ); document.write( "\"x%3E29\" Round to the nearest whole number. A third of a hammer can't be sold.\r
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\n" ); document.write( "\n" ); document.write( "So when \"x%3E29\", we'll have positive profit. So more than 29 hammers must be sold to gain a profit.\r
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\n" ); document.write( "\n" ); document.write( "We're still using the profit function. So \"P%28x%29=6x-170\"\r
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\n" ); document.write( "\n" ); document.write( "Since we want a profit of $100, simply plug in \"P%28x%29=100\".\r
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\n" ); document.write( "\n" ); document.write( "\"P%28x%29=6x-170\" Start with the profit function\r
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\n" ); document.write( "\n" ); document.write( "\"100=6x-170\" Plug in \"P%28x%29=100\"\r
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\n" ); document.write( "\n" ); document.write( "\"270=6x\" Add 170 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"45=x\" Divide both sides by 6\r
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\n" ); document.write( "\n" ); document.write( "So when \"x=45\", we'll have a profit of $100. So 45 must be sold to make a profit of $100.
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