document.write( "Question 771778: If x units of a product cost c dollars to manufacture and earn revenue of r dollars, the value of x where the expressions of c and r are equal is called the break-even quantity, the number of units that produce zero profit. Find break-even
\n" ); document.write( "quantity if c=13x + 20000 and r=15x \n" ); document.write( "
Algebra.Com's Answer #470462 by Edwin McCravy(20056) $\"\"$ $\"About$
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document.write( "If x units of a product cost c dollars\r\n" );
document.write( "to manufacture and earn revenue of r\r\n" );
document.write( "dollars, the value of x where the\r\n" );
document.write( "expressions of c and r are equal is\r\n" );
document.write( "called the break-even quantity, the\r\n" );
document.write( "number of units that produce zero\r\n" );
document.write( "profit. Find break-even quantity if\r\n" );
document.write( "c=13x + 20000 and r=15x. \r\n" );
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document.write( "1. Finst look at the words which tell\r\n" );
document.write( "you what you are to find.  They are the\r\n" );
document.write( "words I have made red below:\r\n" );
document.write( "\r\n" );
document.write( "If x units of a product cost c dollars\r\n" );
document.write( "to manufacture and earn revenue of r\r\n" );
document.write( "dollars, the value of x where the\r\n" );
document.write( "expressions of c and r are equal is\r\n" );
document.write( "called the break-even quantity, the\r\n" );
document.write( "number of units that produce zero\r\n" );
document.write( "profit. Find break-even quantity if\r\n" );
document.write( "c=13x + 20000 and r=15x.\r\n" );
document.write( "\r\n" );
document.write( "2. So now we know what to find, the\r\n" );
document.write( "break-even quantity.  So we look\r\n" );
document.write( "through the words and find what the\r\n" );
document.write( "instructions are to find the break\r\n" );
document.write( "-even quantity.  They are the words I\r\n" );
document.write( "have made red this time:\r\n" );
document.write( "\r\n" );
document.write( "If x units of a product cost c dollars\r\n" );
document.write( "to manufacture and earn revenue of r\r\n" );
document.write( "dollars, the value of x where the\r\n" );
document.write( "expressions of c and r are equal is\r\n" );
document.write( "called the break-even quantity, the\r\n" );
document.write( "number of units that produce zero\r\n" );
document.write( "profit. Find break-even quantity if\r\n" );
document.write( "c=13x + 20000 and r=15x.\r\n" );
document.write( "\r\n" );
document.write( "3. We look at those red words and\r\n" );
document.write( "notice in particular the ones I have\r\n" );
document.write( "made bold and underlined below:\r\n" );
document.write( "\r\n" );
document.write( "If x units of a product cost c dollars\r\n" );
document.write( "to manufacture and earn revenue of r\r\n" );
document.write( "dollars, the value of x where the\r\n" );
document.write( "expressions of c and r are equal is\r\n" );
document.write( "called the break-even quantity, the\r\n" );
document.write( "number of units that produce zero\r\n" );
document.write( "profit. Find break-even quantity if\r\n" );
document.write( "c=13x + 20000 and r=15x.\r\n" );
document.write( "\r\n" );
document.write( "When the words tell us that two things\r\n" );
document.write( "are equal we write them down side by\r\n" );
document.write( "side and put an equal sign \" = \"\r\n" );
document.write( "between them, like this:\r\n" );
document.write( "\r\n" );
document.write( "the expressions of c =  the expression of r\r\n" );
document.write( "\r\n" );
document.write( "Next we look through the words for the\r\n" );
document.write( "expression of c and the expression of\r\n" );
document.write( "r.  They are the ones I have made red\r\n" );
document.write( "below:\r\n" );
document.write( "\r\n" );
document.write( "If x units of a product cost c dollars \r\n" );
document.write( "to manufacture and earn revenue of r \r\n" );
document.write( "dollars, the value of x where the \r\n" );
document.write( "expressions of c and r are equal is \r\n" );
document.write( "called the break-even quantity, the \r\n" );
document.write( "number of units that produce zero \r\n" );
document.write( "profit. Find break-even \r\n" );
document.write( "quantity if \r\n" );
document.write( "c=13x + 20000 and r=15x\r\n" );
document.write( "\r\n" );
document.write( "We notice that the expression for c is\r\n" );
document.write( "13x + 20000 and the expression for r is\r\n" );
document.write( "15x.  So instead of\r\n" );
document.write( "\r\n" );
document.write( "the expressions of c =  the expression of r\r\n" );
document.write( "\r\n" );
document.write( "we write \r\n" );
document.write( "\r\n" );
document.write( " 13x + 20000 = 15x\r\n" );
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document.write( "We subtract 20000 from both sides:\r\n" );
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document.write( " 13x + 20000 = 15x\r\n" );
document.write( "     - 20000       - 20000\r\n" );
document.write( " ------------------------- \r\n" );
document.write( " 13x         = 15x - 20000\r\n" );
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document.write( "We subtract 15x from both sides\r\n" );
document.write( "\r\n" );
document.write( " 13x + 20000 = 15x\r\n" );
document.write( "     - 20000       - 20000\r\n" );
document.write( " ------------------------- \r\n" );
document.write( " 13x         = 15x - 20000\r\n" );
document.write( "-15x          -15x    \r\n" );
document.write( " -------------------------\r\n" );
document.write( " -2x         =     - 20000\r\n" );
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document.write( " We divide both sides by the\r\n" );
document.write( "coefficient of x which is -2\r\n" );
document.write( "\r\n" );
document.write( " 13x + 20000 = 15x\r\n" );
document.write( "     - 20000       - 20000\r\n" );
document.write( " ------------------------- \r\n" );
document.write( " 13x         = 15x - 20000\r\n" );
document.write( "-15x          -15x    \r\n" );
document.write( " -------------------------\r\n" );
document.write( " -2x         =     - 20000\r\n" );
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document.write( " -2x                -20000\r\n" );
document.write( "-----        =      ------\r\n" );
document.write( " -2                    -2\r\n" );
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document.write( "And we cancel the -2's on the left\r\n" );
document.write( "side and divide on the right side\r\n" );
document.write( "and get\r\n" );
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document.write( "   x         =       10000\r\n" );
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document.write( "That's the answer: x = 10000.\r\n" );
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document.write( "Edwin
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