document.write( "Question 985971: Find two numbers that add to 3 and multiply to -40.
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Algebra.Com's Answer #606803 by ikleyn(52803) $\"\"$ $\"About$

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\n" ); document.write( "You need to find two integers x and y from the system of two equations in two unknowns\r
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\n" ); document.write( "\n" ); document.write( " $\"system%28x+%2B+y+=+3%2C%0D%0Ax%2Ay+=+-40%29\"$ .\r
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\n" ); document.write( "\n" ); document.write( "Express y from the first equation y = 3 - x and substitute it to the second equation. You will get \r
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\n" ); document.write( "\n" ); document.write( "x*(3 - x) = -40.\r
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\n" ); document.write( "\n" ); document.write( "Solve it:\r
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\n" ); document.write( "\n" ); document.write( " $\"-x%5E2\"$ + $\"3x\"$ + $\"40\"$ = $\"0\"$ ,\r
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\n" ); document.write( "\n" ); document.write( " $\"x%5E2\"$ - $\"3x\"$ - $\"40\"$ = $\"0\"$ ,\r
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\n" ); document.write( "\n" ); document.write( "The roots are x = 8 and x = -5 (use the quadratic formula).\r
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\n" ); document.write( "\n" ); document.write( "From the first equation, if x = 8 then y = -5.\r
\n" ); document.write( "\n" ); document.write( "Similarly, if x = -5, then y = 8.\r
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\n" ); document.write( "\n" ); document.write( "Answer. The pairs (8,-5) and (-5,8) are the solutions. \r
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