document.write( "Question 1209218: Let a and b be the solutions to 5x^2 - 11x + 4 = -x^2 + 5x - 3. Find
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document.write( "a^2/b + b^2/a \n" );
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Algebra.Com's Answer #847856 by math_tutor2020(3817)![]() ![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "Answer: 520/63\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Explanation\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "5x^2 - 11x + 4 = -x^2 + 5x - 3 \n" ); document.write( "rearranges to \n" ); document.write( "6x^2 - 16x + 7 = 0 \n" ); document.write( "after getting everything to one side.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Then divide each term by the leading coefficient to arrive at \n" ); document.write( "x^2 - (8/3)x + 7/6 = 0 \n" ); document.write( "This is so we have a leading coefficient of 1.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Due to Vieta's Theorems (specifically the quadratic versions), we know these two facts:
\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Based on those two rules we can say \n" ); document.write( "a+b = 8/3 \n" ); document.write( "a*b = 7/6 \n" ); document.write( "Let's call these equations (1) and (2)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Another useful equation we'll need is \n" ); document.write( "a^2+b^2 = (a+b)^2 - 2ab \n" ); document.write( "which is derived from \n" ); document.write( "(a+b)^2 = a^2+2ab+b^2\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Let's label the equation a^2+b^2 = (a+b)^2 - 2ab as equation (3).\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "--------------------------------------------------------------------------\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "= \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "= \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "= \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "= \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "= \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "= \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "= \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "= \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "= \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "= \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "= \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "= \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "= \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "= \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Therefore we determine that \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "I used GeoGebra to verify the solution is correct.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "520/63 = 8.253968 approximately\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "More practice is found here \n" ); document.write( " \n" ); document.write( " |