document.write( "Question 944912: What is an imaginary #, how to solve x^2-4x+8=0
\n" ); document.write( "In what way is the i or imaginery # involved.
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Algebra.Com's Answer #576184 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Imaginary numbers allow ways to deal with $\"+sqrt%28-1%29+\"$
\n" ); document.write( " $\"+x%5E2+-+4x+%2B+8++=+0+\"$
\n" ); document.write( "Complete the square
\n" ); document.write( " $\"+x%5E2++-+4x+=+-8+\"$
\n" ); document.write( "Take $\"+1%2F2+\"$ of the coefficient of
\n" ); document.write( " $\"+x+\"$ , square it, and add it to both sides
\n" ); document.write( "-------------------------------------
\n" ); document.write( " $\"+x%5E2++-+4x+%2B+%28+-4%2F2+%29%5E2+=+-8+%2B+%28+-4%2F2+%29%5E2+\"$
\n" ); document.write( " $\"+x%5E2+-+4x+%2B+4+=+-8+%2B+4+\"$
\n" ); document.write( " $\"+x%5E2++-+4x+%2B+4+=+-4+\"$
\n" ); document.write( " $\"+%28+x+-+2+%29%5E2+=+-4+\"$
\n" ); document.write( "Take the square root of both sides
\n" ); document.write( " $\"+x+-+2+=+sqrt%28+-4+%29+\"$
\n" ); document.write( " $\"+x+-+2+=+sqrt%28+-1%2A4+%29+\"$
\n" ); document.write( " $\"+x+-+2+=+sqrt%28+-1+%29+%2A+sqrt%28+4+%29+\"$
\n" ); document.write( " $\"+x+-+2+=+2i+\"$
\n" ); document.write( " $\"+x+=+2+%2B+2i+\"$
\n" ); document.write( "and also,
\n" ); document.write( " $\"+x+-+2+=+-2i+\"$
\n" ); document.write( " $\"+x+=+2+-+2i+\"$
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\n" ); document.write( "The factors of the equation are:
\n" ); document.write( " $\"+%28+x+-+2+-+2i+%29%2A%28+x+-+2+%2B+2i+%29+=+x%5E2+-+4x+%2B+8+\"$
\n" ); document.write( "You can prove this just by multiplying it out\r
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