document.write( "Question 1118008: Find k and the roots if 2x^2+8x+k=0 and the roots are in the ratio 3:1. \n" ); document.write( "

Algebra.Com's Answer #733192 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "Answer. The roots are -3 and -1. The value of k is 6.\r
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document.write( "The equation is equivalent to  \r\n" );
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document.write( " = 0.\r\n" );
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document.write( "So, the sum of the roots is -4 (the Vieta's theorem) and their ratio is 3.\r\n" );
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document.write( "From it, you get  the roots values  -3 and -1  (mentally).\r\n" );
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document.write( "The value of  is the product of the roots  (-3)*(-1) = 3  (the Vieta's theorem).  Hence, k = 2*3 = 6.\r\n" );
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\n" ); document.write( "To see more solved problems on Vieta's theorem, look into the lesson\r
\n" ); document.write( "\n" ); document.write( " - Using Vieta's theorem to solve qudratic equations and related problems\r
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