document.write( "Question 1050872: What 2 numbers add to get \"1\" and multiply to get \"5\"? \n" ); document.write( "
Algebra.Com's Answer #666489 by rothauserc(4718)\"\" \"About 
You can put this solution on YOUR website!
1) x + y = 1
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\n" ); document.write( "2) x * y = 5
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\n" ); document.write( "solve equation 1) for x
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\n" ); document.write( "x = 1 - y
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\n" ); document.write( "substitute for x in equation 2)
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\n" ); document.write( "(1 - y) * y = 5
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\n" ); document.write( "y - y^2 = 5
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\n" ); document.write( "y^2 -y +5 = 0
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\n" ); document.write( "solve for y by completing the square
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\n" ); document.write( "y^2 -y = -5
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\n" ); document.write( "y^2 -y +(1/4) = -5 +(1/4)
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\n" ); document.write( "(y - (1/2))^2 = -19/4
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\n" ); document.write( "y -(1/2) = square root(-19/4) = (i * square root(19))/2
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\n" ); document.write( "y = (1 + i * square root(19)) / 2
\n" ); document.write( "y = (1 - i * square root(19)) / 2
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\n" ); document.write( "x = 1 - ((1 + i * square root(19)) / 2) = (1 - i * square root(19)) / 2
\n" ); document.write( "x = 1 - ((1 - i * square root(19)) / 2) = (1 + i * square root(19)) / 2
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\n" ); document.write( "we have two sets of solutions
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\n" ); document.write( "x = (1 - i * square root(19)) / 2
\n" ); document.write( "y = (1 + i * square root(19)) / 2
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\n" ); document.write( "x = (1 + i * square root(19)) / 2
\n" ); document.write( "y = (1 - i * square root(19)) / 2
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\n" ); document.write( "checking answers
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\n" ); document.write( "clearly x + y = 1
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\n" ); document.write( "what about xy = 5
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\n" ); document.write( "xy = (1 -(i^2 * 19)) / 4 = (1 - (-19)) / 4 = 20 / 4 = 5
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\n" ); document.write( "our answers check :-)
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