document.write( "Question 98233: The demand and supply equations for a certain item are given by:
\n" ); document.write( "D=-5p+10
\n" ); document.write( "S=-p^2+30p-8
\n" ); document.write( "Find both possible solutions and determine the equilibrium price\r
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\n" ); document.write( "\n" ); document.write( "This is what I have so far:
\n" ); document.write( "-5p+40=-p^2+30p-8
\n" ); document.write( "p^2-35p+48=0
\n" ); document.write( "p^2-36p=-48 I am now unsure of what to do from here.\r
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Algebra.Com's Answer #71391 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
To find the equilibrium, set the equations equal to one another\r
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\n" ); document.write( "\n" ); document.write( "\"-5p%2B40=-p%5E2%2B30p-8\"\r
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\n" ); document.write( "\n" ); document.write( "\"p%5E2-35p%2B48=0\" Get all terms to one side and combine like terms\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for p:\r
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\n" ); document.write( "\n" ); document.write( "Starting with the general quadratic\r
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\n" ); document.write( "\n" ); document.write( "\"ap%5E2%2Bbp%2Bc=0\"\r
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\n" ); document.write( "\n" ); document.write( "the general solution using the quadratic equation is:\r
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\n" ); document.write( "\n" ); document.write( "\"p+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"\r
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\n" ); document.write( "\n" ); document.write( "So lets solve \"p%5E2-35%2Ap%2B48=0\" ( notice \"a=1\", \"b=-35\", and \"c=48\")\r
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\n" ); document.write( "\n" ); document.write( "\"p+=+%28--35+%2B-+sqrt%28+%28-35%29%5E2-4%2A1%2A48+%29%29%2F%282%2A1%29\" Plug in a=1, b=-35, and c=48\r
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\n" ); document.write( "\n" ); document.write( "\"p+=+%2835+%2B-+sqrt%28+%28-35%29%5E2-4%2A1%2A48+%29%29%2F%282%2A1%29\" Negate -35 to get 35\r
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\n" ); document.write( "\n" ); document.write( "\"p+=+%2835+%2B-+sqrt%28+1225-4%2A1%2A48+%29%29%2F%282%2A1%29\" Square -35 to get 1225 (note: remember when you square -35, you must square the negative as well. This is because \"%28-35%29%5E2=-35%2A-35=1225\".)\r
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\n" ); document.write( "\n" ); document.write( "\"p+=+%2835+%2B-+sqrt%28+1225%2B-192+%29%29%2F%282%2A1%29\" Multiply \"-4%2A48%2A1\" to get \"-192\"\r
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\n" ); document.write( "\n" ); document.write( "\"p+=+%2835+%2B-+sqrt%28+1033+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"p+=+%2835+%2B-+sqrt%281033%29%29%2F%282%2A1%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"p+=+%2835+%2B-+sqrt%281033%29%29%2F2\" Multiply 2 and 1 to get 2\r
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\n" ); document.write( "\n" ); document.write( "So now the expression breaks down into two parts\r
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\n" ); document.write( "\n" ); document.write( "\"p+=+%2835+%2B+sqrt%281033%29%29%2F2\" or \"p+=+%2835+-+sqrt%281033%29%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Now break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"p=%2B35%2F2%2Bsqrt%281033%29%2F2\" or \"p=%2B35%2F2-sqrt%281033%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Simplify\r
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\n" ); document.write( "\n" ); document.write( "\"p=35+%2F+2%2Bsqrt%281033%29%2F2\" or \"p=35+%2F+2-sqrt%281033%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "So these expressions approximate to\r
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\n" ); document.write( "\n" ); document.write( "\"p=33.5701586799882\" or \"p=1.4298413200118\"\r
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\n" ); document.write( "\n" ); document.write( "So our possible solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"p=33.5701586799882\" or \"p=1.4298413200118\"\r
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\n" ); document.write( "\n" ); document.write( "However, since \"p=33.5701586799882\" generates a negative supply and demand, the only solution is \"p=1.4298413200118\"
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