document.write( "Question 990548: The difference of two numbers is 2 and the sum of their square twenty what are the numbers
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Algebra.Com's Answer #610553 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "Answer. a) 4 and 2;   b) -2 and -4.\r
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\n" ); document.write( "\n" ); document.write( "x - y = 2;   ----->\r
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\n" ); document.write( "\n" ); document.write( " $\"%28x-y%29%5E2\"$ = $\"4\"$ ,   ----->\r
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\n" ); document.write( "\n" ); document.write( " $\"x%5E2+-+2xy+%2B+y%5E2\"$ = 4,   (recall that    $\"x%5E2+%2B+y%5E2+=+20\"$ ) ----->\r
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\n" ); document.write( "\n" ); document.write( " $\"20+-+2xy\"$ = $\"4\"$ , ----->\r
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\n" ); document.write( "\n" ); document.write( "2xy = 20 - 4 = 16, ----->\r
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\n" ); document.write( "\n" ); document.write( "xy = $\"16%2F2\"$ = 8. ----->\r
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\n" ); document.write( "\n" ); document.write( " $\"system%28x-y=2%2C%0D%0Axy+=+8%29\"$ . ----->\r
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\n" ); document.write( "\n" ); document.write( "x = 2+y ----->\r
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\n" ); document.write( "\n" ); document.write( "(2+y)*y = 8, ----->\r
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\n" ); document.write( "\n" ); document.write( " $\"y%5E2+%2B+2y+-+8\"$ = $\"0\"$ ----->\r
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\n" ); document.write( "\n" ); document.write( "The roots are    $\"y%5B1%5D\"$ = 2,    $\"y%5B2%5D\"$ = -4   (use the quadratic formula or the Viete's theorem). ----->\r
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\n" ); document.write( "\n" ); document.write( "The solutions are   (x,y) = (4.2)   and   (x,y) = (-2, -4).\r
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