document.write( "Question 444589: How do you find a quadratic equation if you are only given the solution? Is it possible to have different quadratic equations with the same solution? \n" ); document.write( "
Algebra.Com's Answer #306433 by solver91311(24713)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Let's assume that and are the roots of some quadratic equation \r
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\n" ); document.write( "\n" ); document.write( "Then with a little algebra we can see that and .\r
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\n" ); document.write( "\n" ); document.write( "Reversing the Zero Product Rule, we can write:\r
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\n" ); document.write( "\n" ); document.write( "Apply FOIL\r
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\n" ); document.write( "\n" ); document.write( "Then let , , and and substitute:\r
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\n" ); document.write( "\n" ); document.write( "The only fly in the ointment is that you can take any real number, say and apply it as a factor:\r
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\n" ); document.write( "\n" ); document.write( "You still have the same roots to the equation, but when you multiply it out you get:\r
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\n" ); document.write( "\n" ); document.write( "Which means that there are an infinite number of quadratic equations with a given pair of roots (or given root with a muliplicity of 2) but they only differ by a factor common to all three terms in the trinomial representation of the quadratic.\r
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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