document.write( "Question 1004969: The problem says to find all the solutions of the equation with the given value of x as a solution... I am so lost\r
\n" ); document.write( "\n" ); document.write( "x^3+3x^2+16x-20=0
\n" ); document.write( "x=-2+4i
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Algebra.Com's Answer #621337 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
\"x%5E3%2B3x%5E2%2B16x-20=0\"\r
\n" ); document.write( "\n" ); document.write( "using zero product theorem, we can write the 3rd degree function as \r
\n" ); document.write( "\n" ); document.write( "\"%28x-x%5B1%5D%29%28x-x%5B2%5D%29%28x-x%5B3%5D%29=0\"\r
\n" ); document.write( "\n" ); document.write( "given:
\n" ); document.write( "\"x%5B1%5D=-2%2B4i\"...if you have this root, you have to have \"x%5B2%5D=-2-4i\" too (complex roots always in pairs)\r
\n" ); document.write( "\n" ); document.write( "then we have\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-%28-2%2B4i%29%29%28x-%28-2-4i%29%29%28x-x%5B3%5D%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%2B2-4i%29%28x%2B2%2B4i%29%28x-x%5B3%5D%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%2B2x%2B4xi%2B2x%2B4%2B8i-4xi-8i-16i%5E2%29%28x-x%5B3%5D%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%2B2x%2B2x%2B4%2B16%29%28x-x%5B3%5D%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%2B4x%2B20%29%28x-x%5B3%5D%29=0\"\r
\n" ); document.write( "\n" ); document.write( "so, \r
\n" ); document.write( "\n" ); document.write( "\"x%5E3%2B3x%5E2%2B16x-20=%28x%5E2%2B4x%2B20%29%28x-x%5B3%5D%29\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%5E3%2B3x%5E2%2B16x-20%29%2F%28x%5E2%2B4x%2B20%29=%28x-x%5B3%5D%29\"\r
\n" ); document.write( "\n" ); document.write( "-----------------(\"x-1\"
\n" ); document.write( "\"%28x%5E2%2B4x%2B20%29\"|(\"x%5E3%2B3x%5E2%2B16x-20\")
\n" ); document.write( "-------------------\"x%5E3%2B4x%5E2%2B20x\"........subtract
\n" ); document.write( "--------------------\"0-x%5E2-4x\"...........bring down \"-20\"
\n" ); document.write( "-------------------...\"-x%5E2-4x-20\"
\n" ); document.write( "-------------------...\"-x%5E2-4x-20\"...subtract
\n" ); document.write( "-------------------...........\"0\"......reminder\r
\n" ); document.write( "\n" ); document.write( "so, third product is \"%28x-x%5B3%5D%29=x-1\"=>\"x%5B3%5D=1\"\r
\n" ); document.write( "\n" ); document.write( "and your equation is factored as following:\r
\n" ); document.write( "\n" ); document.write( "\"%28x%2B2-4i%29%28x%2B2%2B4i%29%28x-1%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "and, roots are:
\n" ); document.write( "\"x%5B1%5D=-2%2B4i\",
\n" ); document.write( "\"x%5B2%5D=-2-4i\", and
\n" ); document.write( "\"x%5B3%5D=1\"\r
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