document.write( "Question 770348: What adds to make 5 and multiplies to get -3 \n" ); document.write( "

Algebra.Com's Answer #469448 by Edwin McCravy(20055) $\"\"$ $\"About$

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What adds to make 5 and multiplies to get -3
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document.write( "Let x and y be the answers:\r\n" );
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document.write( "x + y = 5\r\n" );
document.write( "   xy = -3\r\n" );
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document.write( "Solve the first for y\r\n" );
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document.write( "    y = 5 - x\r\n" );
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document.write( "Substitute it in the second\r\n" );
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document.write( "   xy = -3\r\n" );
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document.write( "x(5 - x) = -3\r\n" );
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document.write( "5x - x² = -3\r\n" );
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document.write( "0 = x² - 5x - 3\r\n" );
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document.write( "Use the quadratic formula since that doesn't factor:\r\n" );
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document.write( "x =  \r\n" );
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document.write( "x = \r\n" );
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document.write( "x = \r\n" );
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document.write( "x = \r\n" );
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document.write( "That's two answers:\r\n" );
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document.write( " x =  and x = \r\n" );
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document.write( "Substituting in y = 5 - x\r\n" );
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document.write( " y = 5 -   and y = 5 -  \r\n" );
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document.write( "y =  -   and y =  -  \r\n" );
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document.write( "     y =   and y = \r\n" );
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document.write( "So there is really only one solution since \r\n" );
document.write( "those just reverse the roles of x and y.\r\n" );
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document.write( "Answer:   and  \r\n" );
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document.write( "Checking:\r\n" );
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document.write( "Add them:\r\n" );
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document.write( "      .\r\n" );
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document.write( "Multiply them:\r\n" );
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document.write( "      .\r\n" );
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document.write( "Edwin

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