document.write( "Question 153209: Can someone help me out, please? Thank you!\r
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\n" ); document.write( "\n" ); document.write( "The owners of a parking garage have determined that their weekly revenue and cost in dollars are given by the following:\r
\n" ); document.write( "\n" ); document.write( "R(x) = 56x - 2x^2
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Algebra.Com's Answer #112727 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Remember, \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( "which is symbolically:\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=%2856x+-+2x%5E2%29-%2824x+%2B+101%29\" Plug in \"R%28x%29+=+56x+-+2x%5E2\" and \"C%28x%29+=+24x+%2B+101+\"\r
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\n" ); document.write( "\n" ); document.write( "\"P%28x%29=56x+-+2x%5E2-24x+-+101\" Distribute the negative.\r
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\n" ); document.write( "\n" ); document.write( "\"P%28x%29=-2x%5E2%2B32x-101\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "Now the break even point occurs when you neither gain money nor lose money. In other words, break even point happens when the profit is zero. So this means that the break even point occurs when \"P%28x%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"0=-2x%5E2%2B32x-101\" Plug in \"P%28x%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic equation in the form of \"ax%5E2%2Bbx%2Bc\" where \"a=-2\", \"b=32\", and \"c=-101\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for x\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4ac+%29%29%2F%282a%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%2832%29+%2B-+sqrt%28+%2832%29%5E2-4%28-2%29%28-101%29+%29%29%2F%282%28-2%29%29\" Plug in \"a=-2\", \"b=32\", and \"c=-101\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-32+%2B-+sqrt%28+1024-4%28-2%29%28-101%29+%29%29%2F%282%28-2%29%29\" Square \"32\" to get \"1024\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-32+%2B-+sqrt%28+1024-808+%29%29%2F%282%28-2%29%29\" Multiply \"4%28-2%29%28-101%29\" to get \"808\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-32+%2B-+sqrt%28+216+%29%29%2F%282%28-2%29%29\" Subtract \"808\" from \"1024\" to get \"216\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-32+%2B-+sqrt%28+216+%29%29%2F%28-4%29\" Multiply \"2\" and \"-2\" to get \"-4\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-32+%2B-+6%2Asqrt%286%29%29%2F%28-4%29\" Simplify the square root (note: If you need help with simplifying square roots, check out this solver) \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-32%2B6%2Asqrt%286%29%29%2F%28-4%29\" or \"x+=+%28-32-6%2Asqrt%286%29%29%2F%28-4%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the answers are \"x+=+%28-32%2B6%2Asqrt%286%29%29%2F%28-4%29\" or \"x+=+%28-32-6%2Asqrt%286%29%29%2F%28-4%29\" \r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"x=4.33\" or \"x=11.67\" \r
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\n" ); document.write( "\n" ); document.write( "So the break even points occur when the price is either $4.33 or $11.67
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