document.write( "Question 426848: I need help I have solve this quadratic equation, and I want to know if its right is there a way to check?\r
\n" ); document.write( "\n" ); document.write( " $\"2x%5E2-4x-3=0\"$ ...my answer is x=1+ - 2sqrt(5).\r
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Algebra.Com's Answer #297109 by robertb(5830) $\"\"$ $\"About$

You can put this solution on YOUR website!
Divide both sides of the equation by 2, to get $\"x%5E2-2x-3%2F2+=+0\"$ . For complex or radical roots, the conjugate must also be a root. The conjugate of the root that you got is $\"1+%2B+2sqrt%285%29\"$ .\r
\n" ); document.write( "\n" ); document.write( "The sum of the roots must be equal to -(-2), or 2. This is true, as $\"%281+-++2sqrt%285%29%29+%2B+%281+%2B+2sqrt%285%29%29+=+2\"$ .
\n" ); document.write( "The product of the roots must be -3/2. This is not true, as $\"%281+-++2sqrt%285%29%29%2A%281+%2B+2sqrt%285%29%29+=+1+-+4%2A5+=+-19\"$ .
\n" ); document.write( "Hence the root that you got is incorrect.\r
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