document.write( "Question 1013018: Find four roots of the following equation:\r
\n" ); document.write( "\n" ); document.write( "2x^4 +5x^2 = 207\r
\n" ); document.write( "\n" ); document.write( "* I plugged into my calculator and only got 2 roots, x=-3 and x=3, but how do you get the rest? Thanks :)
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Algebra.Com's Answer #629176 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
\"2x%5E4+%2B5x%5E2+=+207\" write in standard form\r
\n" ); document.write( "\n" ); document.write( "\"+2x%5E4%2B5x%5E2-207+=0\"\r
\n" ); document.write( "\n" ); document.write( "Factor:\r
\n" ); document.write( "\n" ); document.write( " \"+2x%5E4%2B5x%5E2-207+=0\"\r
\n" ); document.write( "\n" ); document.write( "The first term is, \"2x%5E4\" its coefficient is \"2\" .
\n" ); document.write( "The middle term is, \"5x%5E2+\" its coefficient is \"5\" .
\n" ); document.write( "The last term, \"the constant\", is \"-207+\"\r
\n" ); document.write( "\n" ); document.write( " Multiply the coefficient of the first term by the constant \"+2+%28-207%29+=+-414+\"\r
\n" ); document.write( "\n" ); document.write( "Find two factors of \"-414\" whose sum equals the coefficient of the middle term, which is \"+5\": these are \"-18\" and \"23\" \r
\n" ); document.write( "\n" ); document.write( " Rewrite the polynomial splitting the middle term using the two factors found above, \"-18\" and \"23\":
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\n" ); document.write( " \"+2x%5E4+-+18x%5E2+%2B+23x%5E2+-+207=0\" ............group first two terms together and second two terms together\r
\n" ); document.write( "\n" ); document.write( " \"%282x%5E4+-18x%5E2%29+%2B+%2823x%5E2+-207%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"+2x%5E2%28x%5E2+-+9%29+%2B+23%28x%5E2+-9%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"%282x%5E2%2B+23%29%28x%5E2+-+9%29=0\"\r
\n" ); document.write( "\n" ); document.write( "solutions:\r
\n" ); document.write( "\n" ); document.write( "if \"2x%5E2%2B+23=0\" =>\"2x%5E2=-+23\" =>\"x%5E2=-+23%2F2\" =>\"x=sqrt%28-+23%2F2%29\"=>\"x=++i%2Asqrt%28+23%2F2%29%29\"\r
\n" ); document.write( "\n" ); document.write( "two complex solutions are: \"x=i%2Asqrt%2823%2F2%29\" and \"+x=-i%2Asqrt%2823%2F2%29+\"\r
\n" ); document.write( "\n" ); document.write( "if \"%28x%5E2+-+9%29=0\" =>\"x%5E2+=9\" =>\"x=sqrt%289%29\" =>
\n" ); document.write( "two real solutions: \"x=3\" and \"x=-3\"\r
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