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 :) \n" ); document.write( "

Algebra.Com's Answer #629171 by ikleyn(52799) $\"\"$ $\"About$

You can put this solution on YOUR website!
.
\n" ); document.write( "Find four roots of the following equation:\r
\n" ); document.write( "\n" ); document.write( "2x^4 +5x^2 = 207
\n" ); document.write( "--------------------------------------------------\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "

\r\n" );
document.write( "Introduce new variable for your convenience, y = .\r\n" );
document.write( "\r\n" );
document.write( "Then your equation takes the form\r\n" );
document.write( "\r\n" );
document.write( " = .\r\n" );
document.write( "\r\n" );
document.write( "Apply the quadratic formula. You will get\r\n" );
document.write( "\r\n" );
document.write( " =  =  = .\r\n" );
document.write( "\r\n" );
document.write( "So,  = 9,  = .\r\n" );
document.write( "\r\n" );
document.write( "Now you need to solve this two quadratic equations:\r\n" );
document.write( "\r\n" );
document.write( "1)   = 9. It has two solutions:  x =   and  x = .\r\n" );
document.write( "\r\n" );
document.write( "2)   = . It has two solutions:  x =   and  x = .\r\n" );
document.write( "\r\n" );
document.write( "Thus you got four solutions of your original equation.\r\n" );
document.write( "

\n" ); document.write( " \n" ); document.write( "

\n" );